The story was famously inspired by Ed Gein, a real-life necrophile and murderer from Plainfield, Wisconsin. Gein robbed graves and used body parts to adorn his house or fashion furniture and crockery – even a “woman suit” made from stitched-together skin. Tobe Hooper claimed, possibly stretching the truth, that he had family in Plainfield who told him Gein stories.

Daniel Pearl describes real anxieties about rural Texas – about what might await them beyond their hippie safe haven in Austin. “Oh my God, if we ever break down and the rednecks get their hands on us, we’re done for!” he says. “That was a real harboured fear.”

Hooper and Henkel’s script – called “Leatherface” – got support through Warren Skaaren, the head of the Texas Film Commission. It was Skaaren who came up with the name, The Texas Chain Saw Massacre. “All of us except for Tobe thought it was terrible!” says Pearl. The title, hardly subtle, says it all – and Texas was crucial. “It says, ‘Get ready to f______ rumble… get ready for some crazy s___,’” laughs Pearl.

Hooper and Henkel set up a company named Vortex and initially cobbled together $60,000, most of which came from an investor named Bill Parsley. Vortex passed over 50 per cent of the film to Parsley’s company, MAB. Daniel Pearl helped find another investor and pushed the budget up to $80,000. Production began in the blistering Texan summer of 1973.

Pearl estimates the average age of the crew – made up from aspiring local filmmakers – was around just 23 or 24 years old. Actress Teri McMinn was just 22 at the time, performing in local stage productions. “I was quite put off,” she says. “Chainsaws and meat hooks…?!” She doesn’t recall even seeing a script until they began shooting.

Teri played Pam (“The first girl on a meat hook!”) and joined fellow youngsters Sally (Marilyn Burns), Franklin (Paul Partain), Kirk (Bill Vail), and Jerry (Allen Danziger) – all fresh meat destined for the chopping block.

It was an ordeal from the get-go, with the actors and Tobe Hooper trapped in a baking hot van for nearly four days. Playing the embittered, obnoxious wheelchair-bound Franklin, Paul Partain stayed in character – so odious, that it’s almost a blessed relief when Leatherface takes the chainsaw to his guts.