In the fifth and final season, Neolution is pushing the boundaries of science beyond what anyone thought possible. But at what cost? The mysterious P.T. Westmoreland is the key to all of it. Seemingly 170 years old, he is on the brink of bringing his project to its sinister conclusion. For Sarah and her sisters, this is the start of a deadly endgame that will have extreme consequences, not just for them, but for the future of the entire human race....

Sarah is on the run from a bad relationship when a lookalike stranger commits suicide right in front of her. Sarah sees a solution to all her problems by assuming the dead woman's identity and clearing out her bank account. Instead, she stumbles into a thriller mystery, and uncovers an earth-shattering secret: she is a clone. She learns there are more like her, genetically identical individuals, nurtured in wildly different circumstances, and someone...

Season two hits the ground running with Sarah in a desperate race to find her missing daughter Kira. Her scorched earth tactics spark a war with pro-clone Rachel, dividing and imperiling all the clones. As Sarah discovers more about her past, mysterious newcomers appear. But can they be trusted?

A mysterious new clone appears this season, linking the current season to the past. Felix is having feelings of separation and loss because of the big revelation that Sarah is actually related to S, while Felix isn't.

Sarah is in a desperate race to find her missing daughter, but her scorched earth tactics spark a war with Rachel, dividing and imperiling all the clones. As Sarah discovers more about her past, mysterious newcomers appear, but can they be trusted?

After the shocking discovery of Project Castor, Sarah and her sister clones are left to battle the top-secret military project producing these lethal male clones. At the same time, Sarah tries to track down her missing twin Helena and an ailing Cosima searches for the key to the synthetic sequences that may keep them all alive. But how far are they willing to go to protect each other and their families, and who can they really trust? Orphan Black...