- Writers: John Fawcett, Graeme Manson, Alex Levine, Kim Coghill, Andrew De Angelis, Jeff Detsky, Adam Higgs, Bob Mackowycz Jr., Elize Morgan, Peter Rowley, Rebecca Sernasie
- Stars: Ari Millen , Dylan Bruce , Evelyne Brochu , Jordan Gavaris , Josh Vokey , Kevin Hanchard , Kristian Bruun , Maria Doyle Kennedy , Skyler Wexler , Tatiana Maslany
Sarah pursues the missing Helena who is held in a faraway compound. Sarah must use her wiles - and acting chops - to deter a Topside investigator who threatens the Leda sisters' lives. Meanwhile, Cosima appears to be rebounding from her illness, while Alison and Donnie face newfound financial woes. But when the menace of Castor rears its head once more, Sarah and her entire family must come together to survive.