ARROW – Thursday, January 18, 2018 at 9pm on CW50 – OLIVER DISCOVERS A SHOCKING TRUTH ABOUT CAYDEN JAMES – Despite losing half his team, Oliver (Stephen Amell) remains confident that he, Felicity (Emily Bett Rickards) and Diggle (David Ramsey) can stop Cayden James (guest star Michael Emerson) and Black Siren (Katie Cassidy). However, when he discovers one of Cayden’s secrets, he decides to team up with an unlikely ally. Meanwhile, Dinah (Juliana Harkavy) spends time with Vince (guest star Johann Urb). James Bamford directed the episode written by Ben Sokolowski & Emilio Ortega Aldrich (#610). Original airdate 1/18/2018.