During the first half of our special two-hour event, there's a lot of set-up. At Seattle Grace, Meredith's stepmother visits the clinic to try to resolve her acid reflux and the resulting hiccups. Some wonder drug helps temporarily, but Meredith ends up suggesting a surgical procedure. It seems to have worked, but she ends up coming back with complications.

Meanwhile, both Cristina's mother and Burke's mother have descended on their little love nest to plan a big, fancy wedding. Although Cristina agreed to marry Burke on the assumption that it would be a very small ceremony, he didn't really believe her and enlisted both mothers to plan the wedding. Cristina is uncharacteristically passive, and asks Meredith, Izzie, and Callie to be her bridesmaids. But once she realizes that Burke is in on the whole deal, she seems a bit more resistant.

In other Seattle Grace news, Crush undergoes a neurological exam to try to identify the source of her amnesia, and Derek uncovers some kind of cerebral bleeding. It will take surgery to resolve it, and there's a chance that surgery can restore her memories. Meredith tries to convince Derek that she's now a happy shiny person, and he seems to buy it. And Mark is all sad because Addison has taken an unexpected leave of absence to go to a fertility clinic in Los Angeles.

Addison is there because she wants to make a change in her life, and has decided that having a baby is the best way to do it. While Addison's in L.A., she seems to have a small breakdown, and hears voices. She also discovers that while she spent the last year wallowing in her own misery and ignoring her friend, said friend also got divorced. While Addison is catching up with her friend and her ex-husband, she helps out in a complicated surrogacy situation -- it seems the surrogate had sex with a bunch of people the same week she was implanted with a fertilized egg, and nobody knows who the father is. To top it off, there are serious complications with the pregnancy. And after Addison delivers this news to the surrogate and all the other interested parties, her friend tells her that she's most likely infertile.

Fresh off the news that she's infertile, Addison ends up helping to deliver the surrogate's baby, and then puts all of the potential mothers and fathers in their places so that they remember that the two lives are important. Mother and baby ultimately end up alive and well, and the surrogate is going to let all the would-be parents be a part of the baby's life. And as for the motley group of doctors there, it turns out they all have complicated friendships, lives, and loves just like they do up in Seattle; it's just that the weather is sunnier. As Addison leaves, she's offered the conveniently empty ob/gyn office they have available, and she ponders it while flirting with super-hot Tim Daly.

Back up North with the dysfunctional doctors we know and love, things are rocky. Crush goes into surgery, and they discover that she can speak three additional languages. The surgery is successful and her bleeding is stopped, but she is heartbroken to realize that she didn't regain any of her memories. Alex is there the whole time, however, and helps her through it even though he can't seem to maintain any semblance of a normal relationship with anyone for whom he has feelings. Speaking of non-normal romances, Burke and Cristina move forward with the wedding plans. He seems to be getting worried about the fact that she meant it when she said she didn't want a big wedding, and along with Mama being around and buzzing in his ear all the time, he finally snaps. He sends the mothers away, Cristina finds a dress, and they somehow both end up unexpectedly happy and calm. I'm sure that will be temporary. Izzie assures Callie that she's fine being in a wedding with her, but then breaks down with George and basically begs him not to leave the hospital, which ends in them making out. But the worst news is saved for last: Susan's complications continue to get worse, until they need to rush her into surgery.

Meredith has the task of having to tell her father that his wife is dead, and he responds by slapping her and basically blaming her for what happened. She copes by doing tequila shots with Izzie and Alex later, which Derek sees them doing from the window; he ends up walking away instead of going inside. So just when it looked like Meredith's life was finally starting to come together and be a little bit happy, it begins to fall apart again just about as horribly as possible.