Stephen Amell Oliver Queen, Green Arrow Actor David Ramsey John Diggle, Spartan Actor, Director Emily Bett Rickards Felicity Smoak, Overwatch Actor Echo Kellum Curtis Holt, Mister Terrific Actor Rick Gonzalez Rene Ramirez, Wild Dog Actor Juliana Harkavy Dinah Drake, Black Canary Actor Katie Cassidy Laurel Lance, Black Siren Actor, Director Colton Haynes Roy Harper, Arsenal Actor Kirk Acevedo Ricardo Diaz Actor Sea Shimooka Emiko Queen Actor LaMonica Garrett The Monitor Guest Star Rila Fukushima Tatsu Guest Star Willa Holland Thea Guest Star Byron Mann Guest Star Grant Gustin The Flash Guest Star Katherine McNamara Mia Guest Star Audrey Marie Anderson Lyla Guest Star Joseph David Jones Connor Guest Star Ben Lewis William Guest Star Charlie Barnett Connor's brother Guest Star Greg Berlanti Executive Producer Marc Guggenheim Executive Producer, Writer Andrew Kreisberg Executive Producer David Nutter Executive Producer Laura Belsey Director Antonio Negret Director Tara Miele Director Jill Blankenship Writer Oscar Balderrama Writer Beth Schwartz Writer Benjamin Raab Writer Rebecca Bellotto Writer Deric A. Hughes Writer Rebecca Rosenberg Writer Elizabeth Kim Writer Jeane Wong Writer James Bamford Director