So, it's some period of time after Meredith had her near-death experience and her mother died. She's buried her mother (well, cremated her actually) and is returning to work after recovering from her accident. And who should show up at the hospital? Her father and stepmother, worried and wanting to spend time with Mere. She ends up inviting them to her house for a very awkward dinner. It gets even more awkward when Meredith's father mistakes a memory from Meredith's childhood as being from his other daughter's childhood. Whoops. A blown fuse leads to Mere's dad wandering off in the dark while Meredith hangs out and bonds with her stepmother. The evening ends with Meredith actually finding a new friend in her stepmother and then realizing that her father did love her when he fixes a porch swing. (That last bit made more sense in context.)

Meanwhile, the race for Chief of Surgery heats up when Richard invites a hotshot cardio surgeon to come by and hang out. Even better, he's played by Robin Colcord. And then it turns out that he was (a) Cristina's med school professor and (b) Cristina's med school lover. Which opens Cristina up for all kinds of mockery and throws Burke into a jealous tizzy. Apparently, the fact that Cristina once had a thing with another heart surgeon makes Burke question her love for him, placing their engagement in jeopardy. And the presence of an outside competitor for the top job causes the other attendings to act like hyper-competitive jerks, potentially risking the health of Crush and Derek's patient (an old friend of his, natch).

Finally, Alex has moved into Meredith's house, causing Izzie to feel awkward and uncomfortable. And George finally discovers that the reason Callie can afford to live in a fancy hotel on her resident's salary is that she's an heiress. This naturally leads to a fight between the two of them, and she kicks him out of the hotel. He runs back to Meredith's to do some drinking and get some consolation from Izzie. And console him she does, as they wake up naked and in bed together.