Set in 1940 during the battle of the Atlantic, this is the true story of how the crew of the petrol tanker 'San Demetrio' was left with a near impossible task when she was torpedoed by the Germans. After the ship was torpedoed, the crew abandoned ship in three lifeboats. Two are picked up by other ships in the convoy, but the third drifts for days until its crew spies the burning 'San Demetrio' on... the horizon. Do they board the ship, try to put out its fires and get it back to English shores or do they stay in the drifting lifeboat in the hope of being rescued?