We had a feeling that Owen (Kevin McKidd) was hiding something. On last night’s Grey's Anatomy (Season 8, Episode 17: “One Step Too Far”), we learned in the final seconds of the episode that long-suffering married couple Owen and Cristina (Sandra Oh) had yet another tragic problem between them: his infidelity.

Cristina spent most of the episode in a quietly controlled panic, suspecting Owen of cheating on her with the new nurse Emily (Summer Glau). But eventually Emily explained to Cristina (after an epic confrontation on Cristina’s part) that she’s just flirty because she gets bored, and that she has a boyfriend. No funny business there.

But Cristina knew better than to relax after that. As Meredith (Ellen Pompeo) foreshadowed in her final words of Season 8, Episode 16: “If Only You Were Lonely,” our gut feelings should probably be trusted. Owen admitted to cheating, but not to the identity of his other woman.

Do you think it’s someone we already know? Another nurse or doctor at Seattle Grace-Mercy West? Worse, is it a friend of Cristina’s? Or some mystery girl we’ve never seen?

Grey’s Anatomy airs Thursdays at 9 p.m. ET/PT on ABC.

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