As Reign (Odette Annable) continues to terrorize the city, Supergirl (Melissa Benoist) teams up with Saturn Girl (guest star Amy Jackson), and the two recruit Supergirl’s former enemies, Livewire (guest star Brit Morgan) and Psi (guest star Yael Grobglas), to form a team for a mission to Fort Rozz to recover a prisoner who has information on how to defeat Reign once and for all. Meanwhile, Alex (Chyler Leigh) babysits Ruby (guest star Emma Tremblay).