Liv sees much more than visions after consuming the brains of a paranoid patient.
Dean (Jensen Ackles) makes a shocking decision regarding the Mark of Cain that would change not only his life, but Sam’s (Jared Padaleck) too.
Liv (Rose McIver) and Clive (Malcolm Goodwin) investigate the murder of a journalist working on a story linking psychotic episodes in a small number of consumers to the energy drink Max Rager.
Wells (Tom Cavanagh) presents Barry (Grant Gustin) with a life-changing choice.
Mary (Adelaide Kane) risks everything to take down Condé (Sean Teale), even as Francis (Toby Regbo) believes she is turning against France.
In the aftermath of Alaric (Matt Davis) and Jo’s (guest star Jodi Lyn O’Keefe) powerful nuptials, things take a dramatic turn when an uninvited guest shows up, leaving Elena (Nina Dobrev) in terrible jeopardy.
When it comes to the Stynes, Dean (Jensen Ackles) decides to take matters into his own hands. Sam (Jared Padalecki) tries to come to terms with his decision.
Everyone’s lives are in danger as Ra’s al Ghul (guest star Matt Nable) puts forth his final plan.
Liv (Rose McIver) and Clive (Malcolm Goodwin) investigate the mysterious death of a former sniper, Everett (guest star Ronald Patrick Thompson), who has been working as an instructor at a paintball facility.
As Wells (Tom Cavanagh) once again gets the upper hand on the S.T.A.R. Labs team, Barry (Grant Gustin) realizes he needs to make a big move and reaches out to an old foe, Captain Cold (guest star Wentworth Miller), for help.