633 Squadron

633 Squadron has enjoyed an unqualified string of successes. Their luck changes when they are assigned to bomb a German heavy water plant, which is part of the Nazi effort to develop an atomic bomb, in Norway which is shielded by a mountain and guarded by heavy anti-aircraft defences. Their nearly impossible mission is further complicated by a German air raid, the difficult approach to the target and the capture and torture of the underground leader who is assisting the squadron.