Sarah must elude the ruthless pro-clone Rachel and her people while attempting to secure her daughter's release at the same time. While she calls upon Alison for help getting a gun, Cosima is faced with a decision about her future.
A phone call from Kira gives Sarah and Detective Bell a new lead, where Sarah is stunned to learn who is behind her daughter's disappearance. After Aynsley's funeral Alison struggles with her role in her friend's death, and Cosima settles into her new lab.
On the road with Felix and Kira, Sarah turns to a man from her past for a place to hold up. Alison believes she may have a second monitor, and Cosima learns of the death of another clone who had the same symptoms she does.
After Cal helps Sarah escape her captor the two return to her home, hoping to learn why Mrs. S lied about Project Leda. While Sarah infiltrates the belly of the best, Alison finds herself in rehab.
Rachel lashes out at those close to Sarah, ordering Dr. Leekie to withhold a potential treatment from Cosima. Sarah turns to Art for help with her sister, who is planning her own revenge against Rachel.
Sarah and Helena hit the road together in search of a key scientist from the clone experiment, unaware that they are being followed. Alison sees a familiar face when she attends a group therapy session.
After Alison discovers that her new rehab confidante plans to sell her secret to the cops, she calls on Felix and Sarah to intervene. Cosima learns disturbing news about her treatment, and Mrs. S attempts to make a deal with Dyad.
A new clone turns up on Felix's doorstep with information meant for Beth Childs. Rachel reaches out to Delphine after a Dyad employee turns up dead, and Alison confronts a distraught Donnie.
As Cosima takes a turn for the worse Sarah must decide whether to allow her daughter to be subjected to a painful procedure. Donnie and Alison scramble to bury their problem, and Helena finds new purpose among the Prolethians.
After a broken and defeated Sarah hands herself over to Dyad, Siobhan and Cal pool their resources in an attempt to free her. Helena resurfaces at Art's place, and Rachel's attempts to blackmail her father fail horribly. Finally, a new ally reveals a startling aspect of the clone research.