Dashiell Hammett's hard-boiled detective steps out of the pages of The Maltese Falcon and into his own radio show, with Howard Duff trading wisecracks with Lurene Tuttle's perfect secretary Effie. In this fourth broadcast from August 2, 1946, a Dr. Gregory Denolph hires Sam to recover some letters that could incriminate his patient, the famous actress Constance Brent. But when Spade arrives at the doctor's office, homicide is already calling Denolph's death a suicide -- and the doctor's widow is convinced it was murder, with Constance as her prime suspect. A breezy, twisty caper from one of radio's wittiest detective shows -- the Edgar Award-winning series that helped define the noir comedy formula.

Before Mayberry, Andy Griffith was a stand-up comic with a thick Carolina drawl and a knack for spinning a yarn. 'Ain't It So' is a short, folksy monologue from his 1950s Capitol and Colonial Records run -- the wide-eyed country boy puzzling out the everyday with that perfectly timed pause and a singsong 'ain't it so?' Pure plainspoken Americana from the man who would soon become Sheriff Taylor of Mayberry.

From 22 August 1948 on CBS, Howard Duff stars as Dashiell Hammett's hard-boiled private eye Sam Spade in 'The Vaphio Cup Caper.' A priceless ancient Greek gold cup pulls Sam into a tangle of collectors, forgers, and characters who'd happily put a slug in him for it -- with Lurene Tuttle's Effie Perine at the typewriter catching every wisecrack. Classic William Spier-produced detective radio at its sharpest.

From the earliest weeks of Mutual's classic 1946 detective series, Bob Bailey stars as George Valentine -- the ex-GI private eye whose newspaper ad reads, "Danger's my stock-in-trade." A robbery brings a client to his door, and Valentine and his sharp-tongued secretary Brooksie set out to untangle who's pulling the job and who's covering for whom in this 8 November 1946 broadcast.

John Dehner stars as Paladin, the chess-knight gunfighter for hire, in a Gene Roddenberry-penned tale from 30 November 1958. On the road to Wickenburg, Paladin stops in the little town of Bluebell -- and a stretch of bad luck costs him his money, his gun, and his horse, while somehow leaving him with the affections of a woman. Was it a fair exchange? Tune in and decide.

Alan Ladd is Dan Holiday, the novelist who runs a classified ad inviting trouble. In this June 1949 episode, an ex-convict named Johnny Tide returns to his hometown of Watertown with revenge on his mind, and Holiday finds himself walking a tightrope between a paroled man's grudge and the people he means to punish.

The BBC's landmark science-fiction serial Journey Into Space returns with the opening chapter of "The Red Planet," first broadcast 6 September 1954. Captain Jet Morgan faces a press corps of eager reporters as he prepares Discovery and her crew -- Lemmy, Doc, and Mitch -- for an epic flight to Mars. Charles Chilton's space-age adventure was the last BBC radio drama ever to outdraw its television rivals.

The Jack Benny Program turns the spotlight on its longtime announcer in "The Don Wilson Story," a January 10, 1954 CBS broadcast that plays as part affectionate roast and part tribute. The Benny troupe -- Mary Livingstone, Rochester, Dennis Day, Mel Blanc, and bandleader Bob Crosby -- trade gags about Don's hearty laugh, his Lucky Strike pitches, and his improbable twenty-year tenure beside Jack, while the cheapest man in radio milks every moment for a punchline.

From the syndicated 1950s juvenile space serial Planet Man comes 'Three D Dantro,' the eleventh chapter in the adventures of Dantro, lawman of the League of Planets. When the Planet Man's identity is suddenly doubled, Dr. John Darrow, his daughter Pat, and engineer Slats must figure out which Dantro is the real one before an impostor turns the spaceways to chaos. Atomic-age pulp fun for kids of all ages.

From April 24, 1950: NBC's globe-trotting thriller sends Brian Donlevy's Steve Mitchell into the Alaskan cold on the trail of two missing American scientists -- one of them a former Nazi whose loyalties may not have thawed with the war. A pulp Cold War manhunt where the wrong handshake can get a man killed and the right one might save a continent.