Bailey proposes the creation of a free clinic; a Seattle Grace doctor receives a proposal.
Michael must prove Whistler's innocence of an inmate's murder; Michael demands evidence that Sara is alive; Lincoln and Sofia monitor the guards' morning rituals; Mahone gets an offer that may get him out of Sona.
Sherlock's father is implicated when one of his employees is murdered under the guise of a robbery.
Determined to speak with Sara, Michael enlists T-Bag's help to get to the only phone in Sona; Lincoln tries a daring rescue; Whistler comes clean to Michael; Bellick makes an enemy while trying to get back on his feet.
The team searches for the source of a toxic substance that is released into the public.