Geena Davis Geena Davis

Just when I was ready to give Dr. Herman (Geena Davis) the trophy for "Grey's Anatomy's Most Horrible Character Ever," the show had to go ahead and throw in a brain tumor twist.

After cryptically telling Arizona (Jessica Capshaw) that she has to leave work to deal with some "personal issues," Dr. Herman is a complete terror upon her return. She makes Arizona recite notes verbatim while performing a fetal surgery, and thus has everyone convinced that she's trying to set Arizona up for failure in this fellowship — which Arizona heartbreakingly admits to Alex (Justin Chambers) that she basically traded her marriage for. (On the Calzona front, Arizona's been sleeping in the hospital and neither she nor Callie have told anyone about their breakup.)

When Arizona finally stands up to Dr. Horrible Herman, Dr. H confesses that she has an inoperable brain tumor and will be dead in six months. I, for one, did not see that coming. She needs someone to whom she can pass on her knowledge, and Arizona is the lucky (?) chosen one. That's a pretty interesting twist, but Herman's still kind of the worst though, right?

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Here's what else happened in the episode:

Maggie (Kelly McCreary) weirdly still calls Meredith (Ellen Pompeo) "Dr. Grey," so Derek (Patrick Dempsey) suggests a fun little family dinner party so they can all get to know each other — including Maggie's biodad, Richard (James Pickens Jr.). I loved Derek's reasoning: "Zola needs more black people in the family because I'm running out of ways to braid her hair, and Bailey won't show me anymore." But Meredith, Maggie and Richard are all less than thrilled with this idea.

Breaking News: There's someone in Seattle who's more annoying than April (Sarah Drew)! It's April's mother, who's in town for a visit to "help" April and Jackson (Jesse Williams) prepare for the impending birth of their first child. April resents her mother's interference, while terrified dad-to-be Jackson welcomes it. On a related note, Jackson may be the most perfect husband ever. April and her mother eventually reach a détente, but it's probably safe to say that April's happy her mom lives a plane ride away.

Bailey (Chandra Wilson), meanwhile, is dealing with a patient who thinks his chest troubles are merely the result of heartburn. Even I can tell it's not just heartburn that ails him, and if there's going to be one goner in this episode, my money's on this guy.

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Owen (Kevin McKidd) and Callie (Sara Ramirez) operate on a woman who was found by some of her coworkers, severely beaten. They determine that she was the victim of a carjacking — but this was no ordinary carjacking. She's a homeless veteran who's been living in her car, and all her possessions were inside it. Jo (Camilla Luddington) totally relates, and later whines to Alex that he hasn't asked her to move in — i.e. she's technically homeless again. Alex promises her he's not going anywhere, and his home is her home.

After learning that Heartburn Guy actually has a tumor (Note: Apparently you can get cancer from eating too many cheesesteaks?), Bailey freaks out about her own mortality and realizes that she hasn't been following her own advice about living a healthy lifestyle. She decides to start a running routine, but even jogging half a mile leaves her incredibly sore. "No matter when you start something like this, it's going to be hard," Maggie advises her. "But you have to start. Take baby steps." Sounds like the same approach that Maggie should take with Richard, just saying.

Owen, being a military man himself, tells the homeless vet that there are resources she can turn to. And Heartburn Guy dies during surgery (sadface/called it).

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We later learn that Meredith has apparently never thrown a dinner party before and refers to a pot roast a "thing in the oven." (I have never related to Meredith Grey more than I did in this moment.) Then she and Derek have hot shower sex — and leave their guests waiting awkwardly outside. But that gives Maggie and Richard the perfect opportunity to start to take the ~*~*baby steps*~*~ toward building a father/daughter relationship. (See what they did there?) Progress is made — and very sweetly, I might add — even if Maggie does end up ditching the dinner party.

What did you think of this week's episode? Were you surprised by Dr. Herman's revelation? Will Maggie and Richard ever be comfortable around each other? And do you think Derek and Meredith's marriage is on the road to recovery? Sound off in the comments!

Grey's Anatomy airs Thursdays at 8/7c on ABC.