Upon learning that Aunt Edie has passed away, the Hecks board a train to South Dakota to take her to her final resting place.

Peggy is finally trusted with a mission and calls upon her trusted Howling Commandos squad for backup. But her cover could be at risk when SSR Chief Dooley also sends Agent Thompson with her.

Caitlin takes Barry out to a local karaoke bar to help them both find new loves. Caitlin strikes out but Barry meets a sports reporter and asks her out for a date. Cisco considers Hartley’s dangerous offer. The team searches for Shawna, a meta-human with teleportation powers.

Castle takes on a routine P.I. case, but the investigation turns deadly when he witnesses a murder.

When the Gage presentation falls apart, Marty comes up with a last-ditch plan that includes orchestrating a move that a volatile Ellis doesn’t want. Jeannie has a less-than-encouraging meeting with a headhunter regarding her prospects in the job market. Doug petitions to join Clyde and Kelsey’s new business venture.

Louis is gaining leverage in his quest to become a name partner of the firm and the Pearson Specter team is dealing with the fallout of Louis learning Mike’s secret.

Lives are at risk as Clarke and Lexa encounter a new enemy. Bellamy and Lincoln agree to work together to break into Mount Weather. Murphy helps Jaha confront his past. Meanwhile, Indra makes Octavia an offer she can’t refuse.

Arsenal and Diggle confront Laurel about trying to step into her sister’s shoes and warn her to stop before she gets herself killed. However, when Brick kidnaps the city’s Aldermen and threatens to kill them all unless the police evacuate The Glades, it’s all suits on deck. Meanwhile, Ray steps in to help Lance and the police force fight Brick, showing Felicity a new side of her boss. Malcom tells Thea that Ra’s al Ghul is after him and his family and they must leave town immediately.

When Abbott’s old boss, Agent Peterson, threatens Abbott’s career – and possibly his freedom – Jane devises a risky plan to protect his friend’s future.

Peggy may be in more trouble than usual when fugitive Howard Stark suddenly returns for mysterious reasons. And Chief Dooley chases a new clue all the way to Europe that threatens to destroy Peggy’s future at the SSR.