The episode begins where some fans probably wish more episodes would: with Derek in the bathtub. He and Meredith are trying to take it slowly, but they just can't. They love each other too much! He's so McDreamy. So much so that Meredith proclaims herself "bright and sunny" instead of "dark and twisty" from now on. But given some of the goings on at Seattle Grace on this day, that doesn't last too long.
First and foremost is George's father, who's admitted with a broken clavicle. Callie repairs it, but the staff later learns that Mr. O'Malley has Stage 3 cancer of the esophagus and that it has spread to his stomach as well. To top it off, he needs a heart valve replacement first, so he's strong enough to survive the surgery to remove his tumors. Heavy stuff.
George designates Cristina as the intern on his dad's case, and taps Dr. Burke for the heart surgery. Only he's growing suspicious about their tag-team approach in the OR, and is increasingly convinced that Cristina is hiding a secret. She and Burke deny vehemently that anything is amiss, but by the end, it's clear that O'Malley is onto them.
How it plays out when the surgery takes place is anyone's guess, but the whole experience has changed the way Callie views George. She goes out of her way to bond with his brothers, with whom George has nothing in common. Then she tells them about Mr. O'Malley's condition in simple terms, after George was unable to communicate with them. Dr. Torres now wants him back. Whether he's the pig is another story.
A nine-year-old girl is admitted after being backed into by an SUV. Driven by her nanny, who she is much closer to than her career-driven parents. It makes Miranda think about her own choice to continue as a surgical resident after giving birth not so long ago. Addison and Derek never had kids, and while they're trying hard to be amicable towards each other, It's clear the pain of their divorce is lingering. Nevertheless, they try to help Richard through his noticeable depression at work.
The Chief confides in them that Adele wants him to retire, and that he's been spending what little free time he has with Ellis Grey. After meeting with Derek and Addison, who end up lamenting their own marital problems while trying to help Richard's, he realizes he's not ready to give up on his marriage and knows what he must do. The Chief calls Meredith in and tells her he can't see Ellis anymore, even though it makes her happy.
Izzie is shadowing Alex for the day, and Alex is once again Mark's lackey. This isn't all bad, though, as it gives him a chance to spend time with Izzie as he picks up Mark's dry cleaning and runs other errands. They also get to assist with a patient, Frank, who just had pectoral implants -- and who refers to himself in the third-person (a trend Alex and Izzie adopt).
Taking some advice from Frank, who got the new pecs in response to his lady friend joining the gym, Alex decides to go after what he wants. After they had been getting along famously all day, he plants one on Izzie in the stairwell. She rebuffs him, saying she can't. Later, at Joe's, Izzie says she didn't know he still felt that way. Alex apologizes for being an idiot, and says he understands. There's hope for these two yet.
Some couples are moving on, however. As the credits roll, Addison tosses her wedding ring over the edge of a ferryboat. At the same time, Derek and Meredith are back in the bathtub, only acting far from bright and sunny. This time, they're normal, jaded and tired professionals who live stressful lives. Which is okay, because they're only human.