6x1 - Diagnosis: Murder

Mark, Steve, Jesse, and Amanda are all trapped in the rubble of Community General in the aftermath of the bombing. Mark tries to shake off the numbing effects of the explosion in time to save Amanda, who's suffering from a punctured lung and broken collarbone. After the dust settles, the hunt for Caitlin Sweeney begins. It's discovered that the Sweeneys belong to a terrorist organization, R.O.A.R.