Derek is mad at Meredith. George is living back the house, though still not talking to Meredith. Cristina begins the day on a rush from just having been to a major surgery -- and sex to boot. But, though Burke involved in the latter, he's not entirely sharing Cristina's joy. In fact, they're last sexual encounter has left a bad taste in his mouth. Cristina doesn't notice, though, she's too excited about the incoming trauma cases: an exhausted surgical intern at another hospital falls asleep at the wheel of car and causes a three-car accident -- two of the cars contain members one big, loud Southern family -- and all of them need medical attention at SGH.

The injuries seem minor at first, until the glue of the family -- a pregnant young woman -- crashes during a routine CT. She's got devastating injuries. Just about every attending is on her case - including Addison and her new slave Alex. While Izzie spends more time worrying about the now mobile Denny (thanks to his portable LVAD), Alex is charged with merely watching the baby's vital signs during the course of a long, very invasive full body surgery -- a surgery that invokes an ominous occurrence known as the "triangle of death." But when the mother dies on the table, and her baby only has a few minutes left before it dies as well, Alex jumps into action and helps do an emergency C-section to save the baby's life -- and without Addison. George finally talks to Meredith, slowly tearing down that wall, but an even bigger wall is going up between Meredith and Derek -- he pretty much calls her a whore.