Meredith and Derek get one last shot at success in their clinical trial; the surgeons work together to free a boy from a block of cement; Izzie helps Alex care for Rebecca; Lexie uncovers critical information about George's status as an intern.
The team is called away to the Apalachian Trail in Virginia, after a state trooper, discovers a bag of dismembered body parts. Emily Prentiss returns to the BAU.
Tony and Ziva travel to Colombia, where they are joined by Ziva's longtime mentor Monique in the search for missing Marine Lieutenant and Navy Chaplain Wade.
The president green-lights a raid on the homegrown terrorists, while the staff try to negotiate more debates with Bartlet's Republican rival.