Anyone stranded in a desert will be seen to sweat profusely. (In real life, desert air is so dry that sweat evaporates instantly, and is never visible. On the other hand, you will sweat profusely after any exertion in a rain forest, even if the temperature is mild, but how often do you see that in movies?)

If you see a gun, it will be used.

If the heroes are any good at playing pool (basketball, horseshoes, whatever) they will have no trouble walking into any bar (gym, playground, whatever) and finding tough guys who are willing to bet enormous amounts of money on a game, and who will try to beat them up after losing.

When it rains, it pours. You never see a light drizzle in a movie. Anyone exposed to rain will be soaked to the skin in a few seconds.