After an "awesome" night of sex, Erica breaks down into tears. Happy ones, that is. Sex with Callie has made Hahn see what she's missing and she now realizes that she's 100 percent gay. Callie is kinda freaked out.

Torres says she has to go and runs out of Erica's apartment. Erica breaks down into sad tears this time and starts being really mean to peeps.

Callie hooks up with Mark for a booty call and is perplexed to realize that, while the sex with Erica was awesome, it was also awesome with him.

After she explains the problem to Sloan, he points out that there's not really anything wrong with Callie liking boys and girls, but the one important difference between him and Erica is that he knows.

Callie is now a cheater and, while Sloan is totally okay with that, she needs to ask herself whether or not she's okay with that.

Callie decides she's not okay with it and goes to fess up to Erica. Callie tells Erica she wants to be with her, and that means that she has to start by telling the truth. Erica is surprisingly okay with it.

Meanwhile, Izzie and Alex are together ... sort of. He asks her if they're sleeping with other people or he should cancel a date with a random chick.

Izzie gets indignant and calls him an ass. In the hospital locker room, Alex doesn't get why she's upset when he just wants to know if they're all. He just blows it off and says he's gonna hook up later with the other girl.

Later, Alex comes into Izzie's room to demand some answers. She initially starts to blow him, but finally realizes that he actually wants to be exclusive and just doesn't know how to expose himself to ask.

They agree to go steady.

Cristina and Meredith are walking down the halls of Seattle Grace talking when they rsee the Chief introducing Derek and Sloan to the new head of trauma - Owen Hunt! Yang freaks out and hides. Yet the Army surgeon shows little, if any interest in her throughout the episode.

A trauma workshop consists of Hunt whipping out a pocketknife, stabbing four sedated pigs, and telling the doctors to save them however necessary.

Izzie's terrified by what she feels is the unnecessary torture of animals and walks out. The rest of the doctors get to work on the pigs until a set of traumas come into the ER. Only Yang and her interns stay on pig duty.

Hunt rips Izzie about her aversion to animal testing and Izzie comes right back at him, citing "flipper babies" resulting from drugs tested on guinea pigs, which have different physiologies from humans.

They go back and forth until Izzie finally shuts him down by saying that he is free to do what he wishes, but she just doesn't believe in it.

Alex seemingly takes to Hunt the best, showing a real aptitude for the quick and dirty work of trauma surgery when he superglues a man's head wound.

Derek and Mark are less impressed, annoyed that he threw them out of the ER when they came to help and by Alex's superglue method. If Derek hadn't been able to restore blood supply, the man would have been scarred for life.

But Hunt is receptive to their concerns, admitting that Seattle Grace isn't the field and he may need to adjust his approach. He asks them to tell him what they think he could have done better medically.

Cristina and her interns get attached to the pigs while trying to save their lives and name each of them. When they finally stabilize all of them, Hunt congratulates them ... and then tells them to euthanize the pigs.

Yang shows some rare emotion and confronts him in the hall to tell him that it's unfair to make them spend all day saving the pigs just to kill them.

Hunt points out everything that Yang has learned because of the procedures they performed on the pigs and that the pigs would take months to fully recover - it would be cruel to make the pigs live through that.

Yang sees his point, but can't believe he didn't remember her name.

Hunt tells her the story of what's happened since the last time we saw him - his squadron was killed, he was the only survivor, and he was discharged - and says that he tries to only live in the time after that.

Chief takes Bailey onto the roof and tells her - that he considers her his right hand and that he imagines she'll be the next Chief, especially after last week's domino surgery. But she needs to take the lead.

Bailey's all for it, but wonders why they needed to come on the roof for that. A helicopter with a little girl who has inoperable cancer arrives.

Bailey's first challenge will be to find a way to cure her, with her own handpicked team. Obviously, Chief is on it. Bailey selects Meredith, too, because of a weird doll with removable organs that she found at home

The family of the girl has heard of Erica and demands that she be on the surgery team or they're walking out. Bailey insists Erica join despite Hahn's fierce objections.

The team develops a plan to remove all of the major organs, put them on ice, remove the tumor and splice artificial arteries to replace the ones damaged from the tumor removal. Amazingly, they get it done.

Meredith confronts the Chief about his inability to look at her, which has been manifesting itself throughout the episode. The Chief tells her she's imagining things and snaps that she needs to worry less about him.

Later, he admits that Meredith wasn't imagining things - her presence is a reminder to him of cheating with her mother and all the other mistakes in his life. In his words, Meredith is a walking reminder of every failure in his life, even though that's not her fault.

Much more to come! For now, discuss in the Insider's official Grey's Anatomy forum!