Denny needs a heart or else. Izzie and George go crazy trying to get him one. Derek has the life of a friend in his hands as he operates on Burke who has been shot. Burke cannot operate on Denny after Denny's heart stopped and now Denny is in a dire condition. Cristina gets put in charge of the ER and she is worried about Burke.

This episode is the second part of a two-hour season finale. Richard tries to get information from Addison about a family member's condition. Callie and George have a talk about his feelings. Meredith and Derek have a talk about Doc.

As the escape is in progress, Warden Pope and Captain Bellick begin a search to detain the escapees. Michael and co. have to reach the aircraft fast as the police is hot on their heels. Veronica discovers a major piece of evidence that could prove Lincoln's innocence. The Vice President is worried about losing her authority.

Stephen Colbert welcomes the author of "American Theocracy: The Peril and Politics of Radical Religion, Oil, and Borrowed Money in the 21st Century", Kevin Phillips!

Opening/Monologue: Graig opens tonight by talking about yoga and how hippies have ruined everything they latch onto. Going on later to comment further on workout routines in general. Monday's Guests: Daryl Hannah drops by to her new movie, "Keeping Up with the Steins" and give some details on environmentally friendly lifestyle. Later, Sara Ramirez, star of the ABC hit series "Grey's Anatomy," performs and chats with Graig.