But it almost fell apart, right at a crucial moment. The studio initially showed remarkable confidence in Jackson’s talents, greenlighting three huge movies to be shot consecutively. Even more notable is the fact that they trusted Jackson at all, who scored a hit with the drama Heavenly Creatures, but whose previous work consisted of gross-out horror movies Bad Taste and Braindead (aka Dead Alive), as well as the Muppets-inspired sex romp Meet the Feebles. Jackson’s pitch for a vast trilogy won over New Line head Bob Shaye, but the studio lost faith at a key part of the production. And it could have killed Jackson’s vision for one of the most ambitious battle sequences ever put to screen. The Lord of the Rings film trilogy simply wouldn’t have been the same.

Jackson, together with co-writers Fran Walsh and Philippa Boyens, planned the Battle of Helm’s Deep to be the climax to the second film, The Two Towers. The sequence finds several of the characters — including Aragorn (Viggo Mortensen), Gimli (John Rhys-Davies), and Legolas (Orlando Bloom) — defending a castle from Saruman’s rampaging hordes of Uruk-hai. Jackson and his co-writers envisioned the battle as a 40-minute sequence, a show-stopping climax for the trilogy’s middle chapter. It was unlike anything that had ever been filmed at the time…and it was going to be very expensive, so costly it temporarily soured a few relationships on set.

Mortensen has since admitted to being proud of the finished product but miserable while shooting the actual sequences. They consisted of months of “constant hardship,” Mortensen recently told The Telegraph. “I hated it, I enjoyed it, I will always remember it.” Stuntman Sala Baker concurred, telling the paper, “It was the making and breaking of certain people.”

Among those made and (nearly) broke was Jackson himself, who was shooting the sequence during “a period of time when New Line were at their most angry with us in terms of the budget,” said the director. According to The Telegraph, New Line executive Barrie Osbourne had to stay on set to oversee Jackson’s filming. At one point, Barrie climbed to the top of a shooting location to deliver a message from studio head Michael Lynne to Jackson. “Oh, he’s going to threaten to sue you and sell the house from under you to cover the cost overruns,” the director recalled. In response, Jackson shouted, “Just tell Michael Lynne that I’m shooting this fucking film and I’m doing the best job I can, and I’m not going to interrupt my day with a phone call like that.”