Bart Allen travels to the past to escape an apocalyptic future, and crosses paths with members of the Team and fellow speedsters Jay Garrick, Barry Allen and Wally West along with Iris West and Joan Garrick. The Flash family must also deal with Neutron wreaking havoc in Central City. While Bart Allen seems neutralize Neutron, the future still remains apocalyptic.
The secondary plot of the episode features Red Arrow and Cheshire looking for the real Roy Harper. They arrive in a Tibetan monastery, where according to Cheshire's intel Speedy is kept. It's revealed that they have taken their daughter Lian with them. They enter the building and fight themselves past the guards. After defeating them, they open the door that guards were protecting. In a cryogenic pod they find Speedy.