Plot summary
Art receives a call on Beth's old cell phone from Tony, a transgender clone who promised his dying friend, Sammy, that he would deliver a message to Beth. Tony stays at Felix's apartment until Sarah arrives to tell him that Beth is dead and reveals his origin. Tony delivers the message: "Tell Beth to keep the faith. Paul's like me. He's on it. He's a ghost." Alison learns Donnie intends to leave, prompting her to admit to being responsible for Aynsley's death. Donnie confesses to killing Leekie, and the two begin work to cover up the murder.
Sarah and Mrs. S agree to transport Ethan Duncan to Dyad to start work on a synthetic therapy that may cure Cosima of her illness. Ethan reveals to Rachel that the clones were always intended to be infertile, and views Sarah as a "failure." Before leaving, he hands Kira the book The Island of Doctor Moreau, which houses all of his secrets in its margins. As Ethan and Cosima begin to work, Cosima collapses and goes into violent convulsions.
Credits
Adapted from Wikipedia contributors, List of Orphan Black episodes. HTML formatting and reference markers removed.