A script that calls for big movie stars, expensive fighter planes and a natural disaster would hardly faze most Hollywood film directors. For a pair of documentarians, however, capturing these elements on film is something to get excited about.

When Louis Pepe and Keith Fulton set out to make a documentary of the preproduction stages of Terry Gilliam’s film version of “The Adventures of Don Quixote de la Mancha,” they felt sure they could find enough conflict to make an interesting film. Witnessing the film’s cast and crew subjected to one catastrophe after another, ultimately leading to the disintegration of the project, was well beyond the kind of conflict they had hoped to find.

“The first week of any film production is going to be miserable. There’s 150 people who are all learning to work with each other. But you don’t think that this is going to be the end of the film,” Pepe said.

Tensions were already high when Fulton and Pepe arrived on the set of what would ultimately become their wrenching new documentary, “Lost in La Mancha.” The European crew was operating on a pint-sized budget, many of them did not speak the same language, and none of the actors had arrived for crucial rehearsals and wardrobe fittings.

But Gilliam, director of “Brazil,” “12 Monkeys” and “Fear and Loathing in Las Vegas,” had struggled for 10 years to bring “The Adventures of Don Quixote de la Mancha” to the screen and was determined to make the best of a difficult situation. It took an unbelievable series of events over only six days of filming, including a flash flood, NATO bombers doing flybys, and actors falling ill to destroy finally the director’s dream.

The resulting documentary, opening in limited release today, chronicles the often hilarious and eventually heartbreaking struggle of a creative and passionate man unwilling to accept that his fantasies will not become reality. For Fulton and Pepe, the parallels between Gilliam and Don Quixote, the man who fought giants that were really windmills and loved every minute of it, were obvious from the beginning.

“Most of the movies he has made have Don Quixote characters embedded within them,” Fulton said. “Don Quixote has always been the source for Terry Gilliam, and here he was finally going to tackle the source itself.”

The tragedy of Miguel de Cervantes’ classic hero is that at the end, Don Quixote is forced to accept that the things he had seen were only in his mind. Instead of feeling relief that Don Quixote has finally been cured of his insanity, the reader laments the loss of a true adventurer. While any filmmaker would be thrilled to stumble upon a story as compelling as Don Quixote, in the case of “Lost in La Mancha,” the directors had mixed emotions.

“When you’re making a documentary, you’re looking for dramatic things to happen,” Fulton said. “So when the flash flood was occurring, we were excited. You’re getting very high production values for free. But at the same time Lou and I have known Terry for a long time, and suddenly we’re filming his disaster, his worst nightmare.”

Perhaps they all should have known better. In the course of editing their film, Fulton and Pepe stumbled upon an odd piece of both literary and film folklore: The Quixote curse. Owing to a fraudulent version of the second part of his book having been published a year before he completed it, Cervantes included in his final version a warning to anyone who might try to use his character for their own means.

Gilliam was not the first filmmaker to fall victim to the Quixote curse. Orson Welles tried to make his version for 30 years, leaving it still unfinished at the time of his death. Actor Fernando Rey died in the middle of filming a miniseries version for Spanish television. But perhaps these failures have had more to do with the nature of Cervantes’ character than with a centuries old threat.

“I think it’s just the case that Don Quixote as a subject matter is appealing to a lot of filmmakers and writers who like to take on impossible dreams. It appeals to dreamers,” Fulton said.