Oliver finds himself back at Queen Manor; both his parents are alive, he is about to be married to Laurel Lance, and Diggle is the Hood. However, it is revealed that he, Diggle, Thea, Sara and Ray are all being held unconscious inside pods aboard a Dominator spaceship. Meanwhile, Felicity, Curtis and Cisco Ramon try to hack into the Dominators' mainframe using a piece of their technology. The team recovers a necessary device with the help of the Flash and Supergirl, and they manage to locate the others. Oliver begins seeing flashes of his former life, as do Sara and Ray. All five captives soon realize that they are inside a shared hallucination. Their escape attempt is blocked by manifestations of Malcolm Merlyn, Deathstroke, Damien Darhk and their mercenaries, all of whom are defeated by the captives. The captives then leave the dream and awaken inside the ship. Escaping in a shuttle, they are rescued by the Waverider. Ray deduces that the Dominators were gathering information from their minds, using the hallucination as a distraction, to help them complete a special "weapon". The team learns that the Dominator mothership is headed toward Earth.

This episode continues a crossover that begins on The Flash season 3 episode 8 and concludes on Legends of Tomorrow season 2 episode 7.