Oliver decides itâ€™s time for Thea to come back to Starling City, so he packs for Corto Maltese, where Felicity has traced Theaâ€™s whereabouts. Lyla (guest star Audrey Marie Anderson) asks Diggle to go with Oliver because one of her field operatives, Mark Shaw (guest star David Cubitt), has gone dark in Corto Maltese and sheâ€™d like him to look into it. Feeling responsible for Theaâ€™s departure, Roy joins Oliver and Diggle on their journey. Shaw double-crosses Diggle, putting numerous A.R.G.U.S. agents, including Lyla, at risk.
Meanwhile, Laurel meets Ted Grant, and Felicity adjusts to her new job.