Plot summary
Rachel returns to the island, meeting Coady after visiting Susan and Ira's graves. Though Westmorland promised her freedom and called her a daughter she still feels like part of the experiment. Flashbacks reveal she always struggled against it and could never get acceptance as an equal. Mark is brought to the island after making a deal with Coady for a Castor cure, Gracie visits Helena. Westmorland demands Kira be brought to him, and Rachel is horrified to learn her new eye has a camera to let him see and hear everything she does.
Alison returns with a new look and attitude, shocking Donnie; while Cosima and Charlotte show up to continue research into Westmorland's origins. Sarah gets wind of what is planned for Kira and Cosima sends her Westmorland's real identity. Sarah emails this to Rachel at Dyad, but knowing Westmorland is spying, Rachel acts unmoved. Rachel drugs Kira but sends Art a message with her head turned away. Rachel wears an eye patch to release Kira to her family. Rachel exposes Westmorland to the rest of his backers and bloodily cuts out her prosthetic eye.
Credits
Adapted from Wikipedia contributors, List of Orphan Black episodes. HTML formatting and reference markers removed.