Grey's Anatomy returns Thursday, when several ongoing storylines come to a head.

Alex Karev's jealousy when it comes to Jo's man is about to reach critical mass. When he hears she's moving in with him, he can't resist letting her know how he feels about her "d-bag boyfriend.”

Watch what happens when he hears the news - and how he reacts when Cristina calls him out on his true feelings for her and suggests how he might handle the situation a little more proactively.

We wouldn't put it past Karev, even if she's (probably) kidding ...

Meanwhile, Bailey finds herself at the center of a CDC investigation surrounding several of her patients' deaths, forcing Jackson and the rest of the board to address this budding crisis.

As Meredith urges him not to throw Bailey under the bus and to cross that bridge when they come to it, Jackson says they are already on that bridge, and has seemingly different priorities.

Watch a second clip from "Sleeping Monster" right here:

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