Director Rodrigo Cortés milks every drop of claustrophobic panic from the buried-alive scenario in this suspense film about private-contract truck driver Paul (Ryan Reynolds), who awakens in an underground coffin in Iraq with little more than a cellphone and a Zippo lighter at his disposal. Held ransom by insurgents, Paul tries to negotiate with both his captors and the government and military officials promising to rescue him. These characters are heard but never seen---the movie takes place entirely inside the cramped box with Reynolds, who does a fine job of portraying Paul’s ever-shifting emotional landscape. There’s anger, terror and resignation and, most cruelly, hope. Cortes keeps dangling the possibility of escape only to yank it away, until your stomach’s knotted tighter than Paul’s coffin.