Wes Craven's 1977 film The Hills Have Eyes is an unique horror flick about a family of mutant cannibals who waylay travelers in the Nevada desert, robbing and cannibalizing them to survive.
The film is now considered a cult classic and generally thought of as the film that launched Craven's career, but in the beginning The Hills Had Eyes had one major problem- it was originally rated X due to graphic violence.
Craven produced the film on a tight budget, which forced him to get creative- he found the tarantula used in the film on the road and procured a dead dog "from the county" for the scene where Doug finds the family dog's mutilated corpse.
And the grueling conditions of filiming in the Nevada desert made the threat of heatstroke a grim reality for star Michael Berryman:
Berryman, who became a horror icon thanks to this film, was apparently game for just about anything Craven and company wanted him to do, though he personally told the producers he was born with “26 birth defects.” Among those birth defects was a lack of sweat glands, which meant that the intense desert heat was particularly hazardous to his health. He soldiered on, though, even in intense action sequences.
“We always had to cover him up as soon as we finished these scenes,” Craven recalled.
Read 11 Terrifying Facts About The Hills Have Eyes at Mental Floss