Jack's helmet is hit by enemy sniper fire while on a patrol in Afghanistan.. The concussion causes him to sing most everything and use the word fool excessively. Their orders were to go ten klicks and check for enemy activity. Sergeant Evans decides to return to base with the wounded soldier.For Jack it's send in the fools time. On their return the enemy opens up with a heavy machine gun. Jack sings great balls of fools.The captain ask how many of the enemy did they kill. Jacks sings Thirty nine fools and holding..It's medal time.