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 Paul Blackthorne Detective Quentin Lance Actor Kevin Alejandro Sebastian Blood , Brother Blood Guest Star Caity Lotz Sara Lance Guest Star Summer Glau Isabel Rochev Guest Star Colin Salmon Walter Steele Guest Star Cynthia Addai-Robinson Amanda Waller Guest Star Roark Critchlow Clinton Hogue Guest Star Sean Rogerson Peter Guest Star Keri Adams Bethany Snow Guest Star David Nykl Anatoly Knyazev Guest Star Garfield Wilson Ripped Guest Star Greg Berlanti Executive Producer Marc Guggenheim Executive Producer Andrew Kreisberg Executive Producer David Nutter Executive Producer Michael Schultz Director Holly Harold Writer