The Lost Patrol (1934)

A British patrol is crossing the deserts of Mesopotamia during World War I when the commanding officer is suddenly struck down by an unseen sniper. Their sergeant (Victor McLaglen) suddenly finds himself in charge of the surviving members of his regiment, with no idea where they are or what their mission is. Barricaded at a desert oasis and surrounded by enemy snipers, with no way of summoning reinforcements, the sergeant is forced to call for volunteers for a suicide mission.