Some of these pictures and descriptions may give away plot details that you might not want to know before watching the film.
This is a low-budget western with some great New Mexico scenery, a bunch of inexperienced actors who look right for their parts, and made by a good director. I thought that the three women protagonists would make it worth watching since there are few westerns with good roles for women, but it doesn't really work. The best thing I can say is that the movie passes the Bechdel Test for the active presence of women in movies. That means the movie is not entirely sexist, but it doesn't mean it's any good. The snake scenes aren't very elaborate but the second one was very unusual and very funny, but probably terrifying to people who don't like taking care of their business in the outdoors.
The Thornton brothers are a gang of three outlaws who were caught by some Pinkertons after they robbed a bank and hid the money. When we see them escorted into the town of Jericho to be hung, we see a rattlesnake crawling on main street. I figured that would be all we see - and that the director realized you can't make a western without a rattlesnake - a great rule for sure, though most westerns manage without them. But while there is no follow-up on that first rattlesnake, we do see another one later.
The three Thornton wives watch the hangings in town then return to the ranch where they all live together. The town's villianous banker and corrupt sheriff send a bunch of mean, drunken vigilantes to catch the three Thornton widows in order to force them to tell where their husbands hid the bank money, but before they can do that the women shoot it out with them then get on their horses and ride away. That starts the chase part of the movie which is mostly the chase. Besides the posse following the women, there's also a corrupt preacher and his gang of Mexicans, a couple of Pinkerton detectives, a band of Apaches, and a fourth Thornton brother nobody knew was alive, all chasing after them to find out where the money is hidden. They get shot at and tortured along the way. And, in a really crazy twist, the women keep seeing and talking to the ghosts of their dead husbands.
While camped one night, one of the women leaves to go to the bathroom. As she pulls up all her dresses and squats, the ghost of her husband warns her not to pee on a sidewinder under some greasewood below her. She jumps up in fear of the rattlesnake and then stares in surprise at the ghost, who she hasn't seen before. Then she gets jealous of the woman ghost who is with him.
Even though the habitat and location is wrong for a sidewinder, at least the movie uses a real sidewinder in the scene, or an appropriate-looking dummy. The first rattlesnake looks like a Western Diamond-backed Rattlesnake, a native to the area.