Stephen Amell Oliver Queen Actor Katie Cassidy Laurel Lance Actor David Ramsey John Diggle Actor Willa Holland Thea Queen Actor Emily Bett Rickards Felicity Smoak Actor John Barrowman Malcolm Merlyn Actor Paul Blackthorne Captain Quentin Lance Actor Tom Amandes Noah Kuttler , Calculator Guest Star Colton Haynes Roy Harper , Arsenal Guest Star Celina Jade Shado Guest Star Katrina Law Nyssa al Ghul Guest Star Rila Fukushima Tatsu Yamashiro , Katana Guest Star Echo Kellum Curtis Holt Guest Star Jimmy Akingbola Baron Reiter Guest Star Parker Young Alex Davis Guest Star Janet Kidder Ruvé Adams Guest Star Elysia Rotaru Taiana Guest Star Venus Terzo Dr. Schwartz Guest Star Greg Berlanti Executive Producer Marc Guggenheim Executive Producer Andrew Kreisberg Executive Producer David Nutter Executive Producer Kevin Fair Director Speed Weed Writer Beth Schwartz Writer