When Mike takes a humanitarian case with the potential to jeopardize firm business, Harvey must decide how much to rein in his associate. Meanwhile, Jessica wrestles with the distance she’s been forced to put between herself and Jeff Malone. And Louis fights to get the respect a name partner deserves.
After a long reunion weekend with Phil’s old cheer buddies, Claire jumps at the chance to snag the only first class seat left on the return flight home, leaving Phil in coach. Gloria forces Jay to teach Manny how to defend himself against a bully in his cooking class, but when things backfire it seems that the real bully might be someone else. Mitch, Cameron, Pepper and the whole gang throw Sal a belated baby shower.
Clarke begins to question Lexa’s leadership decisions. Abby struggles to help an injured Kane. Indra continues to push Octavia. Meanwhile, at Mount Weather, Jasper steps up into the role of leader, and Cage throws Maya into a life threatening situation.
Malcolm puts Oliver and Thea in a dangerous situation that lands them on Lian Yu with Oliver’s former enemy, Deathstroke. A flashback reveals when Oliver and Maseo returned to Starling City to retrieve the Omega bio weapon, and despite being under strict orders from Amanda Waller not to reveal himself to anyone, Oliver looks in on his family, Laurel and Tommy.
The Heck family learns about Darrin’s marriage proposal to Sue…as well as her response. Meanwhile, Axl attempts to use his intro to Psych class to cure Brick of all of his quirks and tics.
Lisbon accepts Jane’s surprise marriage proposal, but a killer’s quest for revenge may cost them the happy ending they’ve worked so hard to achieve.
Jane agrees to once again pretend to be a renowned psychic and be used as bait in an attempt to lure out a serial killer and give the FBI a chance to apprehend him.
Peggy is cornered and more vulnerable than ever as Leviathan makes their move against her. As the SSR zeroes in on Howard Stark, they may pay the ultimate price as they find their true enemy is closer than they realized.
After the nuclear explosion separates Ronnie and Dr. Stein, Barry and the team believe both men are safe. Caitlin is thrilled to have her fiancé back and prepares to resume their life together while Dr. Stein returns to his wife. When General Eiling targets Firestorm, Ronnie and Dr. Stein must decide if they are safer together or apart. Mason Bridge tells Iris that there is something secretive going on at S.T.A.R. Labs. Dr. Stein gives Barry some important information about time travel.
In the second installment of the Castle two-parter, stakes rise as the 12th Precinct matches wits with serial killers Jerry Tyson (3XK) and Dr. Kelly Nieman. With the clock ticking, Castle and the team must crack the case before the killers claim their next victim.