Sarah and Helena joined forces and decided to go after the Swan Man in an effort to stop Rachel in Orphan Black’s “Ipsa Scientia Potestas Est.”

Rachel Enlists Paul To Be Her New Monitor

Rachel Duncan (Tatiana Maslany) returned home from her trip to Taiwan to a bloody apartment: Daniel, her monitor, is dead. Dr. Leekie (Matt Frewer) blames Rachel for Daniel’s (Matthew Bennett) death, saying her aggressive ways caused Daniel’s murder, but Rachel isn’t backing down. To replace Daniel, Rachel called Paul (Dylan Bruce), who was with her in Taiwan, and gave him the “promotion.”

Aldous reveals to Rachel that he may have found a stem cell treatment for Cosima (Maslany), but Rachel is ruthless. She instructs Leekie not to treat Cosima, to make her suffer until Sarah (Maslany) surrenders. Rachel’s control over Aldous baffles Paul, so Rachel clears up their relationship. Aldous took care of her after her adoptive parents died, but she is now in a higher position than he is in the corporation.

After instructing Paul to plant the weapon Daniel used to kill cops on Felix (Jordan Gavaris), she seduced him.

Helena And Sarah Bond

At the Prolethean compound, Henrik (Peter Outerbridge) and Bonnie (Kristin Booth) punish Grace (Zoé De Grand Maison) for helping Helena (Maslany) escape by sewing her mouth shut until she confesses, and even threaten forcing her to be the surrogate for the egg they took from Helena.

Helena continued on her mission to kill other clones, this episode tracking Rachel and meeting up with Felix and Art (Kevin Hanchard) along the way. She got into position with a sniper rifle, ready to kill Rachel. Before she could pull the trigger, Sarah and Art get to her and beg her to stop.

“Rachel is problem. I fix problem,” Helena said.

Sarah managed to talk Helena down by appealing to their twin bond, and the two came up with a game plan to track down the mysterious Swan Man, who Sarah discovers is none other than Rachel Duncan’s father, Professor Ethan Duncan, a scientist who appears to have faked his death.

Sarah, meanwhile, is trying to keep everyone straight. She gets a call from Paul telling her that if she doesn’t turn herself in to Rachel, along with Helena and Kira (Skyler Wexler), Felix will be charged with murder.

Once she meets up with Helena, she conspires to get Ethan Duncan/Swan Man and trade him for Felix. Sarah and Helena speed off to a place Helena calls “The place of Screams” where they will find Ethan Duncan. Sarah tries to make a deal with Dr. Leekie, promising to return with Ethan Duncan alive. He seems to agree to her terms, but he sends Paul to follow her, suggesting that he intends to double cross Sarah in the end.

Dr. Leekie Gives Cosima Treatment

Getting sicker by the minute, Cosima and Delphine (Evelyne Brochu) heard about the stem cell treatment that could help Cosima, but it is DNA specific. The two women break into Leekie’s office, and he catches them. Surprisingly, Dr Leekie insists that he wants to help and gives Cosima the injections she needs.

He explains to Cosima that he needs her on his side because the lab explosion 20 years ago destroyed the original genome of the clone, and the group is still trying to understand what exactly the clones are.

Orphan Black airs Saturday at 9 p.m. on BBC America.

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