Grey’s Anatomy has been on a mini-hiatus, but it's finally back tonight (April 25) with Season 9, Episode 21: “Sleeping Monster.” To prepare you for tonight’s return, we've rounded up all of the sneak peeks for the episode right here, and taken a close look to see what we can learn from them.

Spoilers ahead, so if you want to be surprised, turn away now!

Hello, CDC. In this first sneak peek, we learn that Jackson has called in the CDC to find out what happened to Bailey's patients, two of whom are dead (and the third is barely hanging on). The other members of the board are not pleased with this decision.

Meredith in defiance. In the same sneak peek, we learn that Jackson wants the other docs to "keep their distance" from Bailey, an order Meredith ignores.

Bailey wants to check on her patients. In both the above sneak peek and the one below, we see that one of Bailey's main goals is to keep checking on her patients. The problem? The CDC doesn't want her to see them — or even touch their files.

 

Credit: YouTube Photo: Grey’s Anatomy Season 9, Episode 21 Sneak Peek: "They Swabbed My Nose!"

Is it about the grafts? In that same sneak peek, Bailey says she thinks the problem is the "grafts." Will she be proved right?

Everyone is getting swabbed. In the above sneak peek, we also learn that every doctor is getting their nose swabbed, which we see in this clip, too.

 

Credit: YouTube Photo: Grey’s Anatomy Season 9, Episode 21 Sneak Peek: Cristina Says No

Meredith's request. In that sneak peek we also learn that Meredith wants to have a natural birth, and thinks Cristina should be in the room with her when it happens. Cristina does not agree.

Jo is moving in. In the sneak peek below, we learn that Jo is moving in with her hot doc boyfriend... and of course, Alex thinks it's a bad idea.

 

Is Alex in love? In the same sneak peek, Cristina insists that Alex is in love with Jo. Will he acknowledge that and make a move, or just stay friends?

Catch the episode tonight, April 25, 2013, at 9 p.m. ET/PT on ABC.

Rebecca Martin is an editor at Wetpaint Entertainment. Follow her on Twitter @BeccaDMartin.