| Stephen Amell | Oliver Queen |
| David Ramsey | John Diggle /
Spartan |
| Willa Holland | Thea Queen |
| Emily Bett Rickards | Felicity Smoak |
| Echo Kellum | Curtis Holt /
Mr. Terrific |
| Josh Segarra | Adrian Chase /
Prometheus |
| Paul Blackthorne | Quentin Lance |
| Rick Gonzalez | Rene Ramirez /
Wild Dog |
| Juliana Harkavy | Dinah Drake |
| Carly Pope | Susan Williams |
| David Meunier | Ishmael Gregor |
| Mike Dopud | Viktor |
| Adrian Holmes | Frank Pike |
| David Nykl | Anatoly Knyazev |
| Kacey Rohl | Alena |
| Laara Sadiq | Councilwoman Emily Pollard |
| Venus Terzo | Dr. Schwartz |
| Keri Adams | Bethany Snow |
| Jagua Arneja | Paramedic
(as Jag Arneja) |
| Marrett Green | Reporter |
| Chenier Hundal | Paul Holt |
| Panta Mosleh | M.E. Holcomb |
| Greg Rogers | Councilman Kullens |
| Ivan Vladikovic | Russian Bodyguard |
| Victor Young | Cop #1 |
| Michael Dorn | Prometheus
(voice) (uncredited) |
| Mick Wingert | Vigilante
(voice) (uncredited) |