As Alison is terrified by Neolution threats made against Donnie, Sarah and Mrs. S question her loyalty to her sisters. While Sarah is distracted, Siobhan sneaks out to seek vengeance. Meanwhile, Cosima and Susan Duncan work together in a final attempt to discover a cure.

Orphan Black Season 4 Episodes...

• s04e01 - The Collapse of Nature
• s04e02 - Transgressive Border Crossing
• s04e03 - The Stigmata of Progress
• s04e04 - From Instinct to Rational Control
• s04e05 - Human Raw Material
• s04e06 - The Scandal of Altruism
• s04e07 - The Antisocialism of Sex
• s04e08 - The Redesign of Natural Objects
• s04e09 - The Mitigation of Competition
• s04e10 - From Dancing Mice to Psychopaths

Orphan Black Show Summary

After witnessing a woman's sleeping, street-wise chameleon Sarah assumes the stranger's identity, who happens to look just like her. Expecting to solve all her problems by cleaning out the dead woman's savings, Sarah is instead thrust headlong into a kaleidoscopic mystery as she realizes the dizzying truth: she and the dead woman are clones.

As Sarah searches for answers, she discovers the chilling fact that there are more people like her out there - genetically identical individuals who were planted in unsuspecting birth parents and nurtured in completely different circumstances. With no idea who created the clones, she'll need to discover the reason in a hurry as an assassin is hugging them one by one.