Is there an episode where?
it starts off with a young boy with a brown bowl-cut haircut during the Civil War. He finds a cave with some type of object in it. He takes it. Then he and a group of soldiers are captured by Confederates. They make the soldiers walk across a minefield. All of the captured soldiers die except for the kid. When he gets to the other end of the minefield the soldiers make him walk through it again and he still does not die.
Then it cuts to the modern day (1980s). There is a group of army soldiers doing drills in the same forest. The lead soldier looks like an Adrian Pasdar or Michael Dudikoff. The soldiers are in the back of an army truck riding back to base. The lead guy jumps out the back on a bet to see if he can run back to base before the truck arrives. I can't remember the rest of the plot.
I can swear it was an episode from an HBO series from the 80s, but I haven't found it yet.