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 , Deathstroke Actor Susanna Thompson Moira Queen Actor Paul Blackthorne Detective Quentin Lance Actor Caity Lotz Sara Lance , The Canary Guest Star Summer Glau Isabel Rochev Guest Star Carlos Valdes Cisco Ramon Guest Star Dylan Neal Dr. Anthony Ivo Guest Star Chelah Horsdal Kate Spencer Guest Star Danielle Panabaker Caitlin Snow Guest Star Michael Daingerfield Ned Foster Guest Star David Nykl Anatoly Knyazev Guest Star Richard Keats Dr. Lockhart Guest Star Greg Berlanti Executive Producer, Writer Marc Guggenheim Executive Producer Andrew Kreisberg Executive Producer, Writer David Nutter Executive Producer Jesse Warn Director Geoff Johns Writer Keto Shimizu Writer