Special Guest Stars Neal McDonough as Damien Darhk Wentworth Miller as Leonard "Leo" Snart / Citizen Cold Guest Stars Jes Macallan as Agent Ava Sharpe Courtney Ford as Eleanor "Nora" Darhk John Noble voices Mallus Graeme McComb as Young Martin Stein Katia Winter as Freydís Eiríksdóttir Emily Tennant as Clarissa Stein (1987) Thor Knai as Leif Erikson Co Starring Hiro Kanagawa as Director Wilbur Bennett Ben Diskin voices Beebo Richard Stroh as Viking Brother Tara Pratt as Woman Ryan Dumontel as Viking Scott Patey as Chuck Daniel Chai as Store Manager William Ford Hopkins as Follower Winter Lily White as Young Lily Uncredited Matt Ryan as John Constantine