SPOILER WARNING: This article contains major spoilers for "Checkmate," the latest episode of "Arrow."
In "Checkmate," the latest episode of "Arrow," Talia returned in present day -- with a vengeance. When Oliver went to visit her training school, he discovered once and for all that she was an al Ghul, and she's none too pleased about the fact that he is the reason her father died. This being the case, she aligned herself with Prometheus and helped him capture Oliver.
When Oliver visited her school at the beginning of the episode, she got straight to the point: she was estranged from her father Ra's al Ghul, but she's pissed that Oliver had a hand in his death. As soon as he crossed her threshold, she told him he shouldn't have come there. Nevertheless, she told him that Prometheus, but only because she knew that information would make him suffer.
But she didn't stop there. Talia traveled all the way to Starling City just to watch Oliver fall. After he rescued Susan, he came to blows with Prometheus and actually managed to hold his own -- that is, until Talia sneaked up behind him and hit him with a sedative. This sedative knocked him out long enough for both Prometheus and Talia to capture him and smuggle him into a prison cell, where he woke up with his wrists shackled to his ankles.
In the promo for "Kapiushon," next week's episode, Oliver is left in Adrian Chase's hands, and Chase immediately goes to work. It seems that Chase will go to great lengths to torture Oliver, from physical pain to threats against people like his son William.
Chase is probably feeling extra vengeful because Oliver brought his wife into the whole mess. Just before he was kidnapped, Oliver brought Chase's wife to the battle, where she was horrified to discover what her husband had done. Chase seemed instantly remorseful and tearfully accepted his weeping wife into arms. However, she was insistent that he turn himself into the police; his response to that was a knife between her ribs, which caused her to die en route to the hospital. Though he was willing to go great lengths to protect his identity, Chase was obviously furious at that turn of events, and he's sure to take that out on Oliver in "Kapiushon."
Starring Stephen Amell as the Emerald Archer, “Arrow” airs Wednesdays at 8 pm ET/PT on The CW. The series also stars Emily Bett Rickards, David Ramsey, John Barrowman, Willa Holland and more.