Arrow 5×06 “So It Begins” Inside – When Prometheus ups his killing spree, Oliver (Stephen Amell) searches for connections between the victims. Felicity (Emily Bett Rickards) and Curtis (Echo Kellum) discover the victims have a mysterious link to Oliver’s past and this new secret could upend his new team. Meanwhile, Thea (Willa Holland) has a heart-to-heart with Lance (Paul Blackthorne), and Felicity considers telling Malone (guest star Tyler Ritter) the truth about her work. John Behring directed the episode written by Wendy Mericle & Brian Ford Sullivan (#506). Original airdate 11/9/2016.