Snow Maiden (S01E08)

Byzantium receives a directive to eliminate Jack Turner, but when their assassination attempt goes awry, Sam is revealed as a double agent and finds herself confined within the house. Turner unveils the incriminating evidence he holds against Byzantium's client, while Sam, who is covertly succumbing to poison, starts to regain haunting memories that clarify why the Hourglass conspirators are intent on her demise.