Leonard Snart AKA Captain Cold returns to Central City with a new hotheaded partner in tow – Mick Rory AKA Heat Wave. The duo plan to steal a multi-million dollar painting, but Cold has another agenda while in town – to set a trap for The Flash. Snart and Mick kidnap someone close to The Flash and threaten to kill them unless The Flash shows up for a battle of fire and ice. Barry tells Joe he isn’t sure he should take on Snart again after the casualties that happened the last time they fought. Meanwhile, Barry asks Dr. Wells, Caitlin and Cisco to help him double his training efforts so he’s ready for the Reverse Flash when he returns to Central City. Iris deals with the aftermath of Barry’s confession, and Cisco makes the CCPD a new shield.

When a young Latin telenovela actress is murdered, Beckett and the team delve into a case that is as flamboyant and full of intrigue as any telenovela. Meanwhile, Castle is hired as private investigator by the show’s sultry star to pursue the case from another angle.

Marty cunningly proves his business savvy when he meets electric car mogul, Ellis Hightower. In desperate pursuit of a new client, Jeannie orchestrates a chance encounter that appears to go terribly awry. Marty accuses Jeannie of being a dishonest person, prompting her to reveal a difficult truth.

Claire is furious about neighbors Ronnie and Amber’s eye-sore of a boat on their front lawn and it soon becomes an all-out war when Phil calls in the “big guns” as back up – his dad Frank and all his retired friends to give them a taste of their own medicine. Elsewhere, Jay is trying to potty train Joe but Gloria does not think he’s ready yet, and Cam secretly takes Lily to clown school behind Mitchell’s back.

Claire is furious about neighbors Ronnie and Amber’s eye-sore of a boat on their front lawn and it soon becomes an all-out war when Phil calls in the “big guns” as back up – his dad Frank and all his retired friends to give them a taste of their own medicine. Elsewhere, Jay is trying to potty train Joe but Gloria does not think he’s ready yet, and Cam secretly takes Lily to clown school behind Mitchell’s back.

Frankie must work at Ehlert Motors for one day in order to collect her pay on an old, uncashed paycheck, Mike offers Sue a part-time job at the quarry, and Mike’s dad attempts to persuade a lazy Axl to help replace the damaged kitchen sink.

A murder investigation becomes personal for Lisbon when she learns that her underachieving younger brother, Jimmy, is being sought as a key witness.

As Agent Carter closes in on Howard Stark’s stolen technology, Peggy’s secret mission could unravel when the SSR arrests Jarvis and a secret is revealed.

After being forbidden to work with Kate Beckett or the 12th Precinct, Castle obtains a P.I. license and shows up unannounced at Beckett’s crime scene, hoping to investigate alongside her as a private eye. But things don’t go as Castle had planned.

Marty is back with a vengeance – ready to grow Kaan & Associates and conquer the consulting world. Revelations of what has occurred since last season begin to explain the ‘new normal’ at K&A. Marty lays down the law to a pregnant Jeannie on her future with the company, and the pod leaves one client in pursuit of a much bigger payday. .