A Breed Apart (1984)

Grizzled character actors Rutger Hauer and Powers Boothe finally go toe-to-toe in the thriller A Breed Apart (1984)! Hauer stars as Jim, a Vietnam veteran who lost his family and is living in seclusion on an island that doubles as a bird sanctuary. Jim's only contact with humanity is a shopkeeper named Stella (Kathleen Turner), but that all changes when a mountain climber named Mike (Boothe) shows up on the island claiming he wants to climb its infamous peek. However, Mike has really been sent to poach the eggs of a rare breed of eagle nesting on the mountain, setting up a conflict for the ages! 

Both of our grizzled leading men bare their buns in the flick, with Rutger Hauer going ass out while banging Kathleen Turner, and Powers Boothe baring his butt (and nearly his cock) in bed with Jayne Bentzen! These two truly are a breed apart!