In Checkmate Oliver (Stephen Amell) gets closer to the truth about Prometheus. Meanwhile, Helix refuses to continue helping Felicity (Emily Bett Rickards) until she does a favor for them.
Ken Shane directed the episode written by Beth Schwartz & Sarah Tarkoff.
Series: Arrow Season 5 Episode 16
Airdate: 15 March 2017 at 8.00pm on The CW