Break on Through

When the nurses at Seattle Grace go on strike, the doctors are forced to work without them. While most of the doctors cross the picket line, George refuses to cross due to his union roots. With Bailey on maternity leave, the interns meet their temporary resident, Dr. Sydney Heron, who is the exact opposite of Dr. Bailey, which Cristina has a hard time adjusting to. Meanwhile, secrets from Izzie's past are revealed as she treats a young, pregnant teen; and Meredith makes a mistake in treating an elderly patient.