Previously on Grey's Anatomy, Meredith (Ellen Pompeo) and Derek (Patrick Dempsey) had break up sex, Norman Shales (Edward Herrmann) was the world's oldest intern, Thatcher Grey chose Lexie (Chyler Leigh) over Meredith, Richard's (James Pickens) niece knew she was dying, Alex (Justin Chambers) kissed Izzie (Katherine Heigl) but she pulled away, and George (T.R. Knight) told Callie (Sara Ramirez) that he slept with Izzie.

Tonight's Grey's Anatomy picks up right after George's confession to Callie. She simply says that she forgives him. He made a mistake, but they took vows, so she forgives him....

What no one knew was that Meredith had an unfaithful husband and children with him. She had caught him with his ex-girlfriend on the eve of her graduation from medical school. Meredith was fixing to go on a date with Derek when she saw him. "Hello, Meredith!" he said.
"Why are you here?" she asked.
"I want you back!" he said.
"I have a boyfriend!" said Meredith.
"Why are you talking to my girlfriend?" asked Derek.
"She's my wife!" said Eric.
"Ex-wife!" said Meredith.
"You never filed for divorce!" said Eric.
As news spread around Seattle Grace, her friends and boyfriend started questioning...