

In Gotham, Barry, Oliver, and Kara were arrested by the GCPD after getting into a fight. While Clark returned to protect Earth-38, Oliver realized that the figure and Deegan were located in Gotham City.

The figure tells the group that something is coming and they will not be able to stop it. After defeating A.M.A.Z.O., Cisco vibed the mysterious figure and Deegan. Cisco Ramon retrieved Oliver and Barry from Earth-38, with Kara and Clark tagging along. Oliver and Barry used each other's abilities to escape and travel to Earth-38 to get help from Kara Danvers and acquainted themselves with her cousin Clark Kent and his girlfriend Lois Lane. Labs, Team Flash did not believe them and locked them up in "The Pipeline". The following day, Oliver Queen and Barry Allen woke up in each other's lives Oliver is the Flash and Barry is the Green Arrow. On Earth-1, the same figure gave the book to Arkham Asylum psychiatrist John Deegan, who used it to rewrite reality according to his will. On Earth-90, the Flash escaped as a mysterious figure used a powerful book to destroy that Earth.

LaMonica Garrett as Mar Novu/The Monitor.Bob Frazer as Roger Hayden/Psycho Pirate.Tom Cavanagh as Harrison Sherloque Wells and Professor Eobard Thawne/Reverse-Flash.Melissa Benoist as Kara Danvers/Supergirl.John Barrowman as Malcolm Merlyn/Dark Archer.Stephen Amell as Oliver Queen/Green Arrow/The Flash.In this new reality, the two heroes are the only ones that know that they are in the wrong lives and have each other's powers. Synopsis The three-night event begins with Arkham Asylum doctor John Deegan rewriting reality, which results in Oliver and Barry swapping lives.
