Arrow: [SPOILER] Betrays Oliver in 'Checkmate'

03/15/2017 10:02 pm EDT

In "Checkmate," tonight's episode of Arrow, Team Arrow faced another betrayal -- this time one that was at once more personal to Oliver and, in some ways, more obvious.

Talia al Ghul, the daughter of Ra's al Ghul and sister of Nyssa, may have trained Oliver, as we're seeing in the flashbacks this season, but she's still the daughter of Ra's al Ghul...and she's not stupid. Talia knows that Oliver is responsible for her father's death, and as a result, he's persona non grata when he comes to her for help.

Yes, as you've seen in the trailers, she tells him who Prometheus is -- but she also takes Prometheus's side in the war between the two, hitting Oliver with a tranquilizing agent that allows him to be subdued and taken prisoner by Talia and Prometheus.

Lexa Doig, who plays Talia on the series, recently told ComicBook.com that there's "very little that Talia doesn't know," when asked whether or not she knows Oliver is the one who killed her father, and said that while family are often the ones you fight the most with, they're also the ones you're closest to.

While it seemed like a pretty obvious move to make Talia a villain once audiences learned Doig had been cast in the role, suspicions about her ulterior motives died down a bit when it was revealed that she would be appearing primarily in the flashbacks, and operating as Oliver's final mentor/trainer prior to his return to Lian Yu and eventual rescue.

The idea of Talia being a trainer for Prometheus has been making the rounds as a fan theory since she was first announced.

What her role will be going forward, with Oliver in the custody of Prometheus, is an open question at this point.

OLIVER SEEKS THE TRUTH — 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.

Based on the characters from DC, ARROW is from Bonanza Productions Inc. in association with Berlanti Productions and Warner Bros. Television, with executive producers Greg Berlanti (The Flash, Supergirl), Marc Guggenheim (Eli Stone, Percy Jackson: Sea of Monsters), Andrew Kreisberg (The Flash, Supergirl), Wendy Mericle (Desperate Housewives, Eli Stone) and Sarah Schechter (Supergirl, Blindspot).

MORE: More of The Hood and Dolph Lundgren in "Kapiushon" Photos / Arrow Pits the Bratva Against Prometheus In "Disbanded" / Prometheus Unmasks In Checkmate Sneak Preview

The next episode of Arrow will air Wednesday, March 22 at 8 p.m. ET/PT on The CW.

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