The new residents compete against one another in a surgical contest, and Meredith tackles a medical mystery in the process.

Amy Madigan (Dr. Wyatt), Cheech Marin (Otis), Clea Duvall (Jennifer), Lauren Stamile (Rose), Steven Flynn (Scott), Jason O'Mara (Phillip), Troy Westbrook (paramedic) Guest Star

Six weeks after Derek and Meredith ended their relationship and Derek began dating Rose, Meredith and her fellow residents, Alex, Izzie and Cristina, compete in a surgical contest, with Bailey serving as judge. Meanwhile interns George and Lexie adjust to their new, squalid apartment, and Callie finds a friend in her roommate Cristina's nemesis, Erica Hahn.