Castle and Beckett race to stop a series of events that could lead the U.S. into war, and their efforts continue to put Castle in CIA agent Sophia Conrad’s orbit.

When Robin breaks up with Kevin, Ted confesses his feelings to her. Meanwhile, Barney is on a mission to find something private of Marshall and Lily’s.

When the Pod goes to Washington D.C. to consult for a pharmaceutical company, Marty faces a challenge from April to stay monogamous on the road, which puts Jeannie in the position of having to « take one for the team » and fully satisfy a female client; Jeremiah reveals something serious to April, asking for her discretion until he can tell Marty himself; a jealous Monica drops a huge bombshell on Marty.

Lockhart & Gardner leads a class action suit against a software company that allowed the Syrian government to ‘disappear’ American citizens. Will faces a hard decision in the wake of the Grand Jury proceedings.

As the Fringe team investigates a mentally ill patient who appears to be connected to a series of murders, frightening clues and connections are uncovered that lead Olivia to some shocking revelations.

When a charity worker is killed, Jane has Erica Flynn, a murderer he helped imprison, furloughed in exchange for information she claims to have about the case. Meanwhile, Rigsby and Sarah try to adjust to impending parenthood.

Phil and Claire go overboard with drinks, and divulging personal information, on a night out to celebrate the sale of a house to Mitchell and Cameron’s friends.

Frankie pulls out all of the stops in an effort to get an over-excited Sue tickets to a Justin Bieber concert, Mike is thrilled over Brick’s enthusiasm to win the school’s spelling bee and coaches him for the event, and Axl and his friends attempt to break a road sign’s 15-mile-per-hour speed limit – on foot.

Castle and Beckett pursue a ruthless killer who, they discover, is part of a sinister, international conspiracy. Castle and Beckett are joined on the case by Sophia Turner, a smart, sexy CIA operative who has a complicated past with Castle.

Lily and Marshall invite Robin and Kevin on a Valentine’s Day trip to Vermont. Kevin and Robin use the trip to talk about taking their relationship to the next level. Meanwhile, Barney realizes he has finally met his match.