The old phrase "Be careful what you wish for" certainly rings true for Callie.

Having longed for her partner and ... other sort-of partner to like each other for some time, she finds herself thrown for a loop by Arizona and Mark's "relationship." The two are getting along almost too well, and Callie doesn't even know what to make of the new dynamic, leading to some outstanding Grey's Anatomy scenes.

Two of these four sneak previews from tonight's episode focus on Calzona and Mark's home life, while another hilarious clip shows an overworked Owen trying to make time for ... well, just watch it.

Meanwhile, Alex and Teddy hit an interesting roadblock with a heart patient.

Check out the clips from "Poker Face" and comment below ...

Steve Marsi is the Managing Editor of TV Fanatic. Follow him on Google+ or email him here.