After the nuclear explosion separates Ronnie and Dr. Stein, Barry and the team believe both men are safe. Caitlin is thrilled to have her fiancé back and prepares to resume their life together while Dr. Stein returns to his wife. However, when General Eiling targets Firestorm, Ronnie and Dr. Stein must decide if they are safer together or apart. Meanwhile, Mason Bridge tells Iris that there is something secretive going on at S.T.A.R. Labs and Dr. Stein gives Barry some important information about time travel.