Thornton and Scarlett get word that Meredith has been spotted at the Canandaigua airport boarding a private jet. Trouble is there is no flight plan so they don't know where it is headed. Both the Mercury and the Prometheus clear quarantine inspection but only the mercury departs. Jaffra, JoMac, Lyster and Ursula begin their journey down to Boldibar Prison with Gabby flying escort. Kate and Nelson continue to work on their case and realize that their case and Thornton's may cross over. Simon, Slane and Lenora launch in the deep space STIP to begin their journey back to earth.

Thornton and Scarlett find Meredith’s quad in the woods, but no sign of Meredith. Det. Samuels will have startling news for them.  Kate meets with Holliday and O’Neal for an update on the Lee’s.  Later Barnes will call her with shocking news. The Mercury and the Prometheus dock with the BSS after a disagreement between the Robo4 computers. Simon breaks the news of his relation to Lenora and prepares to depart back to London.  Hanaka and his guard survey Zardoz’s domain and decide whether or not to join him.

Simon tells the Prometheus crew that Lenora is his daughter as they travel to the Boldibar Space Station. Kate and Nelson Survey the two internet hubs in DC to evaluate any threat. Kate Nelson and Pearman compare notes on what Operation Ralph might be. Barnes updates Mrs McMillan on what he found in Chicago…up to a point and Thornton and Scarlett find evidence of Meredith’s location.

The Mercury and the Prometheus have lost contact with Hanaka and head for Boldibar, but something awaits them on the other side of the Boldibar portal. Meanwhile Kate and Nelson go over possible targets in DC. Barnes updates Mrs. McMillan on his trip to Chicago. Thornton and Scarlett follow Meredith to a cabin used by his family. Simon finally breaks the big news to the crew of the Prometheus. It's all happening in Episode 278: "Ambush".

The Mercury and the Prometheus have lost contact with Hanaka and head for Boldibar, but something awaits them on the other side of the Boldibar portal. Meanwhile Kate and Nelson go over possible targets in DC. Barnes updates Mrs. McMillan on his trip to Chicago. Thornton and Scarlett follow Meredith to a cabin used by his family. Simon finally breaks the big news to the crew of the Prometheus.

The crews of the Mercury and Prometheus prepare for a sleep cycle en-route to Boldibar but there is unrest. Kate is unsettled by the fact that her case, Thornton's and Jim's seem to have a common denominator. Barnes and Sam land at BWI and walk into a real shocker. Thornton and Scarlett meet with Uncle Joe to gather more intell on Meredith. Something awaits the Mercury and Prometheus as they clear the Boldibar Portal. It's all happening in Episode 277: "Phone Home."

Kate and Nelson continue to investigate the bombing and discover what the mysterious substance is that they found hidden in the floor. Barnes and Sam witness the gun exchange between McMillan and the Russian but they get interrupted. Thornton makes contact with Windsor's Uncle Joe while Hanaka and crew make a dash for an asteroid belt. It's all happening here in the beginning of season 12 "The Split".

Barnes and Sam witness a confrontation between the Russian arms dealer and McMillan. The Mercury and Prometheus give chase to Hanaka and Zardoz. Thornton interviews the bookie Logan, the man that possibly handled Jon’s bets. Kate and Nelson go back to the crime scene and make a surprising discovery.  Hanaka his guard and Zardoz argue on what to do next.

Barnes and Sam follow McMillan to Chicago and a Country Club in Ft. Sheridan. They witness the passing of something and it leads to a shocking conclusion. The crew of the Mercury gets the Shuttle on board containing JoMac and Slane assesses his condition.  Thornton and Scarlett meet with Jonathan Windsor’s prom date Sandy from back in the day. The crew of the Prometheus prepares the ship to escort the Mercury back to Boldibar. Kate and Nelson learn more about the Lee family and their connection to Kate’s old nemesis Wei Wong.

After a lengthy chase, the Mercury catches up with the stray shuttle with JoMac on board. Hernandez uncovers more information on the couple who own the dry cleaners. The names Wong and Kuo come up much to Kate’s shock. Sam and Barnes arrive in Chicago and tail McMillan to Ft. Sheridan and find him meeting with a shocking player.