Enemies because they were taught to be. Allies because they had to be. Brothers because they dared to be.

Enemy Mine (1985)

Directed by Wolfgang Petersen

A soldier from Earth crashlands on an alien world after sustaining battle damage. Eventually he encounters another survivor, but from the enemy species he was fighting; they band together to survive on this hostile world. In the end the human finds himself caring for his enemy in a completely unexpected way.