In Egypt, Andoheb travels to the Hill of the Seven Jackals in answer to the royal summons of the High Priest of Karnak. The dying priest of the sect explains the story of Kharis to Andoheb, involving the theft of sacred tana leaves that can restore life to the dead Princess Ananka, who Kharis secretly loves. Kharis' penalty upon being discovered is to be buried alive, without a tongue, and the tana leaves are buried with him. During the cycle of the full moon, the fluid from the brew of three tana leaves is to be administered to the creature to keep him alive. Should despoilers enter the tomb of the Princess, a fluid of nine leaves will restore movement to the monster.

Meanwhile in 1940, down on his luck archaeologist Steve Banning and his sidekick, Babe Jenson, discover the remnants of a broken vase in a Cairo bazaar. Banning is convinced it is an authentic ancient Egyptian relic, and his interpretation of the hieroglyphs on the piece lead him to believe it contains clues to the location of the Princess Ananka's tomb. With the support of the eminent Dr. Petrie (Charles Trowbridge) of the Cairo Museum, but against the wishes of Andoheb, who is also employed by the museum, Banning seeks funds for his expedition. Banning and Jenson meet an American magician, Solvani (Cecil Kellaway), who agrees to fund their quest. His daughter Marta is not as convinced, thanks to a prior visit from Andoheb, who brands the two young archeologists as frauds. The expedition departs in search of the Hill of the Seven Jackals, with the Solvanis tagging along. In their explorations, they stumble upon the tomb of Kharis, finding the mummy along with the tana leaves, but find nothing to indicate the existence of Ananka's tomb. Andoheb appears to Dr. Petrie in the mummy's cave and has the surprised scientist feel the creature's pulse. After administering the tana brew from nine leaves, the monster quickly dispatches Petrie and escapes with Andoheb, through a secret passageway, to the temple on the other side of the mountain. The creature continues his periodic marauding about the camp, killing an Egyptian overseer and eventually attacking Solvani and kidnapping Marta. Banning and Jenson set out to track Kharis down, with Jenson going around the mountain and Banning attempting to follow the secret passage they have discovered inside the tomb.

Andoheb has plans of his own. Enthralled by Marta's beauty, he plans to inject himself and his captive with tana fluid, making them both immortal. Jenson arrives in the nick of time, and guns down Andoheb outside of the temple, while Banning attempts to rescue the girl. However, Kharis appears on the scene and Banning's bullets have no effect on the immortal being. Marta overheard Adoheb tell the secret of the tana fluid and tells Banning and Jenson that Kharis must not be allowed to drink any more of the serum. When the creature raises the tana serum to his lips, Jenson shoots the container from his grasp. Dropping to the floor, Kharis attempts to ingest the spilled life-giving liquid. Banning seizes the opportunity to overturn a brazier onto the monster, engulfing it in flames. The ending has the members of the expedition heading happily back to the United States with the mummy of Ananka, and the spoils of her tomb.

Big-game hunter and wealthy zoologist Eric Gorman (Lionel Atwill) is an insanely jealous husband who uses his animal knowledge to dispose of his impulsive wife's lovers. The film opens in an Indian jungle with Gorman using a needle and thread to sew a colleague's mouth closed after having discovered that he had kissed his wife, and then he seals the man's fate by abandoning him in the jungle with the wild beasts. Gorman later pretends to be surprised at hearing that the man had been eaten by tigers. Both Gorman and his wife Evelyn (Kathleen Burke) then return to America aboard a ship packed with captured animals he intends to add to his collection at a major zoo. On the ship, Evelyn has a relationship with Roger Hewitt (John Lodge), which she tries to hide from her husband. Naturally, the murderously jealous Gorman finds out. Once back in the States, he begins to plot a way to get rid of Hewitt.

The zoo is beginning to run into financial trouble and the new press agent, Peter Yates (Charles Ruggles), a man terrified of most of the zoo's animals and considered to be an alcoholic, suggests hosting a fundraising dinner for the rich to raise funds and awareness. The last straw is when Gorman finds his wife at Hewitt's apartment where they have been plotting their escape and her divorce. Gorman invites Hewitt to the dinner and uses it as the perfect opportunity to dispense his vengeance by poisoning Hewitt with mamba venom. He had obtained the poison after asking the zoo's laboratory doctor, Jack Woodford (Randolph Scott), to work on finding an antitoxin for the snake's fatal bite.

When Hewitt unexpectedly dies at the fundraising dinner, Evelyn accuses her husband of being the murderer. Outraged, Gorman attacks her, but she is able to escape into his office where she finds a mechanical mamba head seeping with real mamba poison in his desk. She now knows for a fact that he killed Hewitt and takes the snake head with the intention to find Dr. Woodford. However, Gorman finds his wife, swears he did everything because he loves her, and prevents her from revealing his crime by throwing her to the alligators, where she is torn to shreds.

Dr. Woodford then becomes suspicious and accuses Gorman of murdering both his wife and Rodger Hewitt. Gorman disposes of Dr. Woodford by attacking him with the mechanical snake head just as he had done to Hewitt. The doctor's assistant Jerry (Gail Patrick) gives Woodford a shot of the antitoxin he had created for the mamba poison in time to save his life. She also realizes that Gorman is responsible for the apparent mamba attack when he tries to stop her, and has the zoo's alarms set off. A police chase ensues as Gorman is pursued through the zoo. Gorman releases big cats from the carnivore house in the hopes of keep back the police, but it backfires and a group of them chases Gorman, and forces him into the cage of a boa constrictor, who then slowly kills and devours him.

Wilfred Glendon (Henry Hull) is a wealthy and world-renowned English botanist who journeys to Tibet in search of the extremely rare selenotropic plant known as mariphasa lupine lumina. While there, he is attacked and bitten by a creature later revealed to be a werewolf, although he succeeds in acquiring a specimen of the mariphasa. Once back home in London he is approached by a fellow botanist, Dr. Yogami (Warner Oland), who claims to have met him in Tibet while also seeking the mariphasa. Yogami warns Glendon that the bite of a werewolf would cause him to become a werewolf as well, adding that the mariphasa is a temporary antidote for the disease.

Glendon does not believe the mysterious Yogami. That is, not until he begins to experience the first pangs of lycanthropy, first when his hand grows fur beneath the rays of his moon lamp (which he is using in an effort to entice the mariphasa to bloom), and later that night during the first full moon. The first time, Glendon is able to use a blossom from the mariphasa to stop his transformation. His wife Lisa (Valerie Hobson) is away at her aunt Ettie's party with her friend, former childhood sweetheart Paul Ames (Lester Matthews), allowing the swiftly transforming Glendon to make his way unhindered to his at-home laboratory, in the hopes of acquiring the mariphasa's flowers to quell his lycanthropy a second time. Unfortunately Dr. Yogami, who is revealed to be a werewolf, sneaks into the lab ahead of his rival and steals the only two blossoms. As the third has not bloomed, Glendon is out of luck.

Driven by an instinctive desire to hunt and kill, he dons his hat and coat and ventures out into the dark city, killing an innocent girl. Burdened by remorse, Glendon begins neglecting Lisa (more so than usual), and makes numerous futile attempts to lock himself up far away from home, including renting a room at an inn. However, whenever he transforms into the werewolf he escapes and kills again. After a time, the third blossom of the mariphasa finally blooms, but much to Glendon's horror, it is stolen by Yogami, sneaking into the lab while Glendon's back is turned. Catching Yogami in the act, Glendon finally realizes that Yogami was the werewolf that attacked him in Tibet. After turning into the werewolf yet again and slaying Yogami, Glendon goes to the house in search of Lisa, for the werewolf instinctively seeks to destroy that which it loves the most.

After attacking Paul on the front lawn of Glendon Manor, but not killing him, Glendon breaks into the house and corners Lisa on the staircase and is about to move in for the kill when Paul's uncle, Col. Sir Thomas Forsythe (Lawrence Grant) of Scotland Yard, arriving with several police officers in tow, shoots Glendon once. As he lies dying at the bottom of the stairs, Glendon, still in werewolf form, speaks: first to thank Col. Forsythe for the merciful bullet, then saying goodbye to Lisa, apologizing that he could not have made her happier. Glendon then dies, reverting to his human form in death.

Dracula's Daughter begins a few moments after Dracula ends. Count Dracula has just been destroyed by Professor Van Helsing (Edward Van Sloan). Van Helsing is arrested by two Whitby policemen, Sergeant Wilkes (E. E. Clive) and constable Albert (Billy Bevan). Van Helsing is sent by the Whitby police to Scotland Yard, where he explains to Sir Basil Humphrey (Gilbert Emery) that he indeed did destroy Count Dracula, but because he had already been dead for over 500 years, it cannot be considered murder. Instead of hiring a lawyer, he enlists the aid of a psychiatrist, Dr. Jeffrey Garth (Kruger), who was once one of his star students.

Sergeant Wilkes leaves the Whitby gaol to meet an officer from Scotland Yard at the train station. Meanwhile, Dracula's daughter, Countess Marya Zaleska (Gloria Holden), enters the gaol and mesmerises Albert with her jewelled ring and with the aid of her manservant, Sandor (Irving Pichel), steals Dracula's body from the Whitby gaol, and after tossing salt on the pyre, ritualistically burns Dracula's body, hoping to break her curse of vampirism. However, Sandor soon begins to discourage her, telling her that all that is in her eyes is "death". She soon gives in to her thirst for blood. The Countess resumes her hunting, mesmerising her victims with her exotic jewelled ring. After a chance meeting with Dr. Garth at a society party, the Countess asks him to help her overcome the influence she feels from beyond the grave. The doctor advises her to defeat her cravings by confronting them, and the Countess becomes hopeful that her will, plus Dr. Garth's science, will be strong enough to overcome Dracula's malevolence.

The Countess sends Sandor to fetch her a model to paint. He sees a pretty young woman, Lili (Nan Grey), and follows her onto a bridge. The woman pauses at the railing looking despondent. Sandor promises her food, warmth, and money. She hesitates, but Sandor explains that he seeks her for his mistress. Lili returns with Sandor. Countess Zaleska initially resists her urges, but succumbs and attacks her. Lili survives the attack and is examined by Dr. Garth through hypnosis; she reveals enough information to let Dr. Garth know that Countess Zaleska was who attacked her, but she suffers heart failure and dies. The Countess gives up fighting her urges and accepts that a cure is not possible; she lures Dr. Garth to Transylvania by kidnapping Janet Blake (Marguerite Churchill), his secretary, with whom he has a playfully antagonistic relationship, but now realises that he cares for her. Zaleska intends to transform Dr. Garth into a vampire to be her eternal companion. Arriving at Castle Dracula in Transylvania, Dr. Garth agrees to exchange his life for Janet's. Before he can be transformed, Countess Zaleska is destroyed when Sandor shoots her through the heart with an arrow as revenge for her breaking her promise to make him immortal. He takes aim at Dr. Garth, but is shot dead by a Scotland Yard policeman, who along with Van Helsing, has followed Dr. Garth from London.

After Jean Thatcher (Ware) has been injured in a car accident, her father, Judge Thatcher (Hinds) and beau Jerry (Matthews) implore retired surgeon Dr. Richard Vollin (Lugosi) to perform a delicate operation to restore her to health. Vollin agrees and is successful; he befriends the spirited and grateful Jean, in the process revealing his passion for all things related to Edgar Allan Poe, including his homemade collection of torture devices inspired by Poe's works (such as a pit, pendulum with crescent razor, shrinking room, etc.), and identifying the raven as his talisman.

After Vollin reveals his growing love for Jean to her father, the Judge quickly discourages him from the affair. Angered, Vollin hatches a plan when Edmond Bateman (Karloff), a murderer on the run, comes to his home asking for a new face so he may live in anonymity. Vollin admits to not being a plastic surgeon, but says he can help Bateman, and asks him to help in exacting revenge on the Thatchers, which he refuses. Bateman explains that he feels his antisocial behavior is a result of having been called ugly all his life, and he hopes a new face may gave him a chance to end it. Vollin performs the surgery, but instead turns Bateman into a disfigured monster, promising only to operate again on Bateman when Vollin's revenge is exacted. Bateman finally reluctantly agrees.

Vollin hosts a dinner party, among which Jean, Jerry, and the Judge are guests. One by one, the guests are caught in the Poe-inspired traps. Ultimately, Bateman is shot by Vollin as he rescues Jean and Jerry, but throws Vollin into the shrinking room where he perishes, and the guests escape.

Count Dracula arrives at the castle home of Dr. Franz Edelmann. The Count explains that he has come to Visaria to find a cure for his vampirism. Dr. Edelmann agrees to help, believing that vampirism can be cured by a series of blood transfusions. The Count agrees to this, and Edelmann uses his own blood for the transfusions. After, The Count has his coffin placed in the castle basement. That night, Lawrence Talbot arrives at the castle demanding to see Dr. Edelmann about a cure for his lycanthropy. Talbot is told to wait, but knowing the moon is rising, Talbot has himself incarcerated by the police. Inspector Holtz asks Edelmann to see Talbot, and as the full moon rises, they both witness his transformation into the Wolf Man. Edelmann and his assistant Milizia have him transferred to the castle the next morning. Edelmann tells him that he believes that Talbot's transformations are not triggered by the moonlight, but by pressure on the brain, and believes he can relieve the pressure and asks Talbot to wait while he gathers more spores from a plant he believes can cure him. Despondent by the thought of becoming the Wolf Man again, Talbot attempts suicide by jumping into the ocean, only to end up in a cave below the castle.

Edelmann searches for Talbot in the cave where they find the catatonic Frankenstein's monster, still clutching the skeleton of Dr. Niemann. Humidity in the cave is perfect for propagating the clavaria formosa, and a natural tunnel in the cave connects to a basement of the castle. Dr. Edelmann takes the monster back to his lab, but considers it too dangerous to revive him. Meanwhile, The Count tries to seduce Milizia and make her a vampire, but Milizia wards him off with a cross. Edelmann interrupts to explain that he has found strange antibodies in the Count's blood, requiring another transfusion. Edelmann's assistant Nina begins shadowing Milizia and discovers that the Count casts no reflection in a mirror. She warns Edelmann of the vampire's danger to Milizia. Edelmann prepares a transfusion that will destroy the vampire. During the procedure, The Count uses his hypnotic powers to put Edelmann and Nina to sleep and reverses the flow of the transfusion, sending his own blood into the doctor's veins. When they awake, The Count is carrying Milizia away. They revive Talbot and force the Count away with a cross who returns to his coffin as the sun is beginning to rise. Edelmann follows him and drags the open coffin into the sunlight, destroying him.

Edelmann begins to react to Dracula's blood and finds that he no longer casts a reflection in a mirror. Falling unconscious, he sees strange visions of a monstrous version of himself performing unspeakable acts. Edelmann awakens, and tries to perform the operation on Talbot. Edelmann begins leaping into a more monstrous personality, and murders his gardener. When the townspeople discover the body, they chase Edelmann, believing him to be Talbot. They follow him to the castle, where Holtz and Steinmuhl interrogate Talbot and Edelmann. Steinmuhl is convinced that Edelmann is the murderer, and assembles a mob to execute him. Talbot is cured by the operation, but Edelmann again turns into his mostrous self. Edelman revives Frankenstein's monster, with the others witnessing Edelmann's transformation, and Edelmann breaks Nina's neck and tosses her body into the cave. Holtz and Steinmuhl lead the townspeople to the castle where the police attack the monster, but are subdued by the creature. Edelmann kills Holtz by accidental electrocution and Talbot shoots Edelmann dead. Talbot traps the monster under fallen shelving as a fire breaks out, and the townspeople flee the burning castle. The burning roof collapses on the monster.

An animal trainer Fred Mason (Milburn Stone) returns from his latest safari with a horde of animals for his employer John Whipple (Lloyd Corrigan), owner of the Whipple Circus. Among them is Cheela (Ray Corrigan), a gorilla with remarkably human characteristics. Mason's fiancée Beth Colman (Evelyn Ankers) is present at the dock for his return. She tells him of the recent health problems encountered by her sister Dorothy (Martha MacVicar). Beth reflects on taking her sibling to see Dr. Sigmund Walters (John Carradine), an endocrinologist of some standing. Dorothy is staying at Walters’ Crestview Sanatorium for treatment. Fred and Beth arrive at the winter quarters, and Dr. Walters pays a visit. He is extremely interested in Cheela, and inquires about purchasing her. Whipple tells him that she is not for sale. Upon returning to his lab, Walters finds that his latest experiment has resulted in the lab animal's death. He becomes convinced he needs larger animals that possess the “will to live.” Walters enlists the aid of a disgruntled former circus employee to steal Cheela. After the ape is loaded onto his truck, the scientist callously pushes the man into the gorilla's grasp and stolidly watches as the beast wrings his neck.

Back at his lab, Walters and his assistant Miss Strand (Fay Helm) transplant glandular material from Dorothy into Cheela. There was discussion by Miss Strand that Walters has previously grafted the glands of different animals like placing a guinea pig's glands into a rabbit and a frog's glands into a mouse. To the horror of the nurse, the ape transforms into human form (Acquanetta). Telling the doctor that she cannot allow him to continue, Miss Strand informs him that at best he will have “a human form, with animal instincts.” Dr. Walters reaches the conclusion that he will need to place a human brain into his creation to successfully complete his experiment. While watching Mason practice his animal act, an accident occurs. Paula rushes into the cage and saves him from the ferocious felines, who display an unnatural fear of her and retreat from her presence. Mason is dumbfounded and offers the girl a job in his act.

Beth receives a frantic telephone call from her sister who expresses her fear of Dr. Walters and the forthcoming operation. Arriving at the Sanatorium to aid her sister, Beth is pegged by the good doctor as the next brain donor for Cheela. However, she proves resourceful in a pinch, releasing the ape from its cage. Cheela does Walters in and departs the lab, leaving Beth and Dorothy unharmed. Performing his animal act solo, Mason finds himself trapped inside the cage with his unruly subjects. A powerful storm interrupts the performance and the beasts attack the trainer. Cheela comes to his rescue once again and carries him to safety. Unfortunately, a nearby police officer mistakes her intentions and kills Cheela.

In a village of the Bavarian Alps, a young scientist named Henry Frankenstein and his assistant Fritz, a hunchback, piece together a human body.  Frankenstein desires to create a human, giving this body life through electrical devices he has perfected. But he still needs a brain for his creation. 

Henry's fiancée Elizabeth speaks with their friend Victor Moritz about the scientist's increasingly peculiar actions and how he secludes himself. Elizabeth and Victor ask Dr. Waldman for help in understanding Henry's new behavior and Waldman reveals he is aware Dr. Frankenstein wishes to create life. Concerned for Henry, they arrive at the lab just as the scientist makes his final preparations. With a pulley system, Frankenstein and Fritz raise the operating table high in the room, moving it toward an opening at the top of the tower. The creature and Frankenstein's equipment are exposed to the lightning storm and empowered. The hand of Frankenstein's creature begins to move. The scientist triumphantly shouts, 'It's alive!'

Frankenstein's Monster, despite its grotesque form, seems to be an innocent, childlike creation. Dr. Frankenstein welcomes it into his laboratory and asks his creation to sit, which it does. Thinking that it is not fit for society and will wreak havoc at any chance, they leave the Monster locked up, where Fritz antagonizes it with a torch. As Henry and Waldman consider the Monster's fate, they hear a shriek from the dungeon. Frankenstein and Waldman run down and find that the Monster has strangled Fritz. The Monster lunges at the two but they escape, locking the Monster inside. Realizing that the Monster must be destroyed, Henry prepares an injection of a powerful drug and the two conspire to release the Monster and inject it as it attacks. When the door is unlocked the Monster lunges at Frankenstein as Waldman injects the drug into the Monster's back. The Monster falls to the floor unconscious.

Henry collapses from exhaustion, and Elizabeth and Henry's father arrive and take him home. Henry is worried about the Monster but Waldman reassures him that he will destroy it.

With preparations for the wedding completed, Henry is serenely happy with Elizabeth. They are to marry as soon as Waldman arrives. However, Victor rushes in, saying that Doctor Waldman has been found strangled. Henry suspects the Monster. Meanwhile, the Monster enters Elizabeth's room, causing her to scream. When the searchers arrive, they find Elizabeth unconscious on the bed. The Monster has escaped.

Maria's father arrives, carrying his drowned daughter's body. He says she was murdered, and the villagers form a search party to capture the Monster and bring it to justice, dead or alive. In order to search the whole country for the Monster, they split into three groups: Ludwig leads the first group into the woods, Henry leads the second group into the mountains, and the Burgomaster leads the third group by the lake. During the search, Henry becomes separated from the group and is discovered by the Monster, who attacks him. The Monster knocks Henry unconscious and carries him off to an old mill. The peasants hear his cries and they regroup to follow. They find the Monster has climbed to the top, dragging Henry with him. The Monster hurls the scientist to the ground. His fall is broken by the vanes of the windmill, saving his life. Some of the villagers hurry him to his home while the rest of the mob set the windmill ablaze, with the Monster trapped inside.

At Castle Frankenstein, Frankenstein's father, Baron Frankenstein, celebrates the wedding of his recovered son with a toast to a future grandchild.

In a small town bordering a swampy region, unexplained murders and rumors of mysterious happenings surround the swamp-based home of the reclusive but respected Curt Ingston (Morgan). Ingston uses a wheelchair and has invited to his home the three doctors who were trying to cure him when his paralysis set in. Already in the household are his grim-humored butler Rolf; a lecherous chauffeur, Lawrie; a mannish housekeeper, Miss Judd; an Eastern mystic, Agar Singh; and Ingston's allegedly mentally ill sister, Margaret. Outside, the gate is watched by a shrivelled old hunchback called Torque.

Coincident with the arrival of the three male physicians is the appearance of a lady psychiatrist, Dr. Lynn Harper, summoned secretly by Margaret to prove she is not insane and help her secure freedom from the control of Ingston and Miss Judd. She arrives accompanied by a neighbor: mystery-writer Dick Baldwin, who rescued her after her car broke down in the swamp. Neither Ingston nor Miss Judd welcome her presence, but must contend with keeping her overnight until her car can be repaired.

Following dinner, at which Ingston's conviction that the three doctors are directly responsible for his current condition becomes evident, the party witnesses an exhibition of materialization of an Egyptian skeleton by Agar Singh. Dr. Harper is forbidden to meet with Margaret. Then, one by one, the doctors are frightfully killed as they prepare for bed. Suspecting Ingston, Dick and Police Captain Beggs confront him in his room, but discover he is not paralyzed but a quadruple amputee. Suspicion then falls on Lawrie, who was last seen driving a murdered ex-employee of the household back to town, but he, too, winds up dead.

Ultimately, Dick confronts the killer outside the estate as he menaces Lynn, and discovers it is Ingston after all: by studying under Agar Singh, he has learned how to materialize arms and legs, hands and feet for himself, long enough to accomplish his evil deeds. As Dick struggles with him to the death, Margaret sets fire to the unholy house, committing suicide while taking the malevolent Miss Judd with her. As the house burns to the ground, Dick and Lynn are saved by Agar Singh, when Singh shoots Ingston. -Wiki

Struggling sculptor Marcel De Lange (Martin Kosleck) is depressed about events in his life, and decides to commit suicide. Just as he's about to kill himself, he sees a madman, known as "The Creeper" (Rondo Hatton), in the process of drowning, and saves him. Taking the disfigured man into his care, he makes him the subject of his next sculpture and calls it his best creation. When critics denigrate Marcel's work, he has the Creeper start killing them. Marcel becomes obsessed with Joan, a beautiful female reporter who believes the deaths are related. When Marcel invites her over and she sees Marcel's sculpture of The Creeper, she suspects that Marcel knows the killer. Later, Marcel decides that Joan knows too much and commands The Creeper to kill her. The Creeper is reluctant to do, however, when he discovers that Marcel plans to turn him over to the police. The Creeper kills Marcel, and is about to kill Joan when he is shot by the police.