Susan upsets an important client; Renee and Gabrielle reveal secrets about each other; Emma Graham plans a cabaret show.
Cristina, back from her honeymoon trip, searches in vain for Burke; Meredith, Cristina, Izzie and Alex spend their first day as residents with their own groups of interns
Meredith and Derek rediscover the morning-after side of their relationship; the chief learns the hospital has slipped in the national rankings.
The residents and interns treat the victims of a massive explosion at an apartment building, while Alex investigates the cause of the accident.
The new interns are dazzled by the skill level of fellow intern George, while Lexie helps keep his "repeater" status a secret; Meredith half-heartedly helps Lexie with her first emergency patient.
