Oliver wakes up to a life where he never got on The Queen’s Gambit. Robert and Moira Queen are alive and well. Laurel is his loving fiancée and their wedding is imminent. Everything seems perfect, but Oliver starts to notice small imperfections that make him question this new reality. Meanwhile, Felicity and the recruits take on a new threat with help from The Flash and Supergirl.
The crossover starts on Supergirl S02E08 Medusa (I) and The Flash S03E08 Invasion! (II). It continues on DC's Legends of Tomorrow S02E07 Invasion! (IV).
Quest roles:
Katie Cassidy(Laurel Lance / Black Canary), Rick Gonzalez(Rene Ramirez / Wild Dog), Susanna Thompson(Moira Queen), John Barrowman(Malcolm Merlyn), Grant Gustin(Barry Allen / The Flash), Melissa Benoist(Kara Danvers / Supergirl), Carlos Valdes(Cisco Ramon), Caity Lotz(Sara Lance / White Canary), Joe Dinicol(Rory Regan / Ragman), Jamey Sheridan(Robert Queen), Brandon Routh(Ray Palmer), Nick Zano(Nate Heywood), Neal McDonough(Damien Darhk), Erica Luttrell(Dr. Laura Washington / Cyber-woman), Amy Pemberton(Gideon (voice)), Parker Brando(Hoodie)