Rachel issues an ultimatum to Sarah, and the outcome sparks a clash with Kira, who begins exploring her own maturity. Also: Felix reconnects with an old ally to help his family get Kira.
- Abuse Mistake: Type A — the hospital staff suspect Donnie of causing Helena's injury while she's posing as his wife.
- Been There, Shaped History: Westmoreland was a personal friend of Arthur Conan Doyle.
- Big Sister Instinct: When Sarah learns that M.K. hasn't made it to the safe-house, she heads to Felix's apartment to get her, refusing to leave one of her sisters behind. However M.K. doesn't want to leave.
- Cruel and Unusual Death: Ferdinand stomps on M.K.'s chest until she dies.
- The Empath: Kira "feels" M.K. dying and has a Freak Out!. She demands to go with Rachel so she can find out why she's like that.
- Enemy Mine: Ira teams up with Clone Club because Rachel stabbed Susan.
- Healing Factor: Helena's babies seem to have inherited this trait. One of them was stabbed by the branch, but the nurses can't find the wound when they check the ultrasound again.
- I Have Your Wife: Sarah wakes up to find that Kira, Siobhan, Alison, Art, and Cosima are all under Neolution's control.
- I Just Want to Be Normal: Kira, upon realize that she and her family are going into hiding again, refuses to leave because she wants to stay in school and be a regular kid.
- Impaled with Extreme Prejudice: Helena stabs a doctor through the cheek and mouth with a needle while making her escape from the hospital.
- Internal Reveal: M.K. finally tells Sarah that she's sick.
- Mama Bear: The instant Rachel mentions wanting to study Kira, Sarah knocks a cup of tea out of her hand and refuses.
- Spiteful Spit: M.K. spits in Ferdinand's faces as he strangles her.
- Twin Switch: Sarah impersonates Rachel to pick Kira up from school and get her away from Dyad. Kira instantly recognizes her. Then M.K. impersonates... Sarah impersonating Rachel. Ferdinand isn't fooled for long, though.
- We Can Rule Together: Rachel offers this to Sarah — she can live in peace with her family if she cooperates and agrees to live under Neolution surveillance.