Stephen Amell Oliver Queen Actor Katie Cassidy Laurel Lance Actor Willa Holland Thea Queen Actor Colton Haynes Roy Harper Actor David Ramsey John Diggle Actor Emily Bett Rickards Felicity Smoak Actor Manu Bennett Slade Wilson Actor Susanna Thompson Moira Queen Actor Paul Blackthorne Detective Quentin Lance Actor Clé Bennett The Mayor , Xavier Reed Guest Star Bex Taylor-Klaus Sin Guest Star Caity Lotz Sara Lance , The Canary Guest Star Dylan Bruce Adam Donner Guest Star Kevin Alejandro Sebastian Blood , Brother Blood Guest Star Summer Glau Isabel Rochev Guest Star Audrey Marie Anderson Lyla Michaels Guest Star Keri Adams Bethany Snow Guest Star Richard Keats Dr. Lockhart Guest Star David Nykl Anatoly Knyazev Guest Star Greg Berlanti Executive Producer Marc Guggenheim Executive Producer Andrew Kreisberg Executive Producer, Writer David Nutter Executive Producer Eagle Egilsson Director Wendy Mericle Writer