Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
A honeymooning couple take a mule trip to the bottom of the Grand Canyon. Their guide gets bitten several times by a rattlesnake because he must be the stupidest guide in the world not to be able to avoid getting bitten. Then he dies and the mules run away and the happy couple gets lost and the survival adventure story you paid to watch begins.
This is another example of the use of a preposterously vicious rattlesnake attack used only to get rid of a character because the screenwriters are too stupid to think of something that could have really happened to get rid of him. Sometimes I think that more people are killed from venomous snake bites in movies than they are in the real world. Maybe try a piano falling on his head next time. It works in cartoons, and most of them are more believable than this nonsense.