As Roy and Jillian are climbing up the Devils tower monument Roy looses his footing and tumbles down a steep slope, if you look carefully just in front of the rock that Jillian is behind there is a stagehand wearing a head to toe black body stocking(to make him blend into the shadow of the rock) "spotting" for Richard Dreyfuss. You can see the stagehand crouching down and turning his head to watch Richard tumble down the slope