Exhaustion - as well as the entire concept of adulthood - is taking its toll on Meredith. She can barely keep her eyes open at work, as the stress of taking care of her mother, along with the chores and hours of the intern program, are a whole lot to take. During an open heart procedue with Dr. Burke, Meredith's hand slips and she's afraid she's punctured the patient's heart. At first, she says nothing about it.
While assisting Bailey and Webber on a procedue, George discovers a towel left inside a woman from a surgery five years earlier. It turns out that it was Burke's old mistake - will he have to come clean about it to the woman and the hospital? In personal news, Izzie has invited the entire staff to a party at Meredith's because her boyfriend, Hank, is in town.
The heart patient that Meredith may have jeopardized, crashes. Dr. Burke revives her, but Meredith panics and admits her mistake ... in front of the woman's husband. This doesn't exactly please the doctor as the husband is threatening to sue. Even though the fate of the patient is revealed to NOT be related to Meredith's miscue, a meeting is scheduled the next morning to go over what occurred.
When Meredith returns from this hectic day - one also that included a trip to the nursing home to sign some legel documents - her house is abuzz with a giant shindig. While hesitant at first, Meredith joins the fun, gets blasted and ends up making out witu Sheppard in his car. Dr. Bailey catches the half-naked embrace.
As the episode winds down, Izzie breaks up with her boyfriend because her new life as a doctor is just too hectic. Meredith is then left off the hook when Burke admits his five-year old snafu at the meeting and sticks up for the intern, explaining that even the best doctors make mistakes.