Thanks to The Aviator, we all know about Hell’s Angels, Howard Hughes’ 1930 labor of love. So it’s hard to imagine that the war epic—which was reconfigured as a talkie halfway through filming, lost a plagiarism lawsuit against Warner Bros., and saw four deaths on its dangerous set—was not Hughes’ lengthiest venture.

That distinction belongs to Jet Pilot, which began filming in 1949. Conceived as “a Hell’s Angels for the jet age,” Hughes’ final credited work touted the newest aircraft and most daring pilots the U.S. Air Force had to offer … at the time it was filmed. That Hughes sat on it—or, more likely, obsessively edited it—for years and years made it seem like an outdated artifact to critics and audiences by the time it debuted in 1957.

At least Mughal-e-Azam was worth the wait. So much so that crowds outside Mumbai’s Maratha Mandir theater were known to wait in line for days—even fight!—in order to secure tickets for the extravagant Bollywood epic. That’s what happens when anticipation builds for 14 years … (Should we start getting in line for Avatar 2 now?)

The Partition of India, and surrounding unrest, disrupted Mughal-e-Azam’s initial 1946 filming effort. But after the dust had settled and new financiers had been found years later, the 500-day (!!!) shoot on India’s then most expensive production commenced. Like Hughes before him, director K. Asif was tempted too by developing technologies. After filming a few reels in Technicolor in 1958, he lobbied to reshoot the entire black-and-white picture in color. With delays already stretching over a decade, investors pressured the still-lavish feature into theaters by 1960. Now, thanks to a 2004 colorization, the three-hour saga can be enjoyed in vibrant, multi-hued glory.

Was Tippi Hedren the original Carole Baskin? Judging from her dedication to the 1981 big-cat flick Roar, we have to say yes. Yes, indeed.

Following a tour of a Mozambique national park—on which Hedren and her then-husband director Noel Marshall witnessed lions living in abandoned houses—the couple began dreaming up a movie with a similar premise. To make it, though, they decided to bring a little bit of Africa to … Southern California.

After first illegally housing lions in their own residence, the duo built a two-story house for the big cats in a canyon not far from Los Angeles. Construction, development, animal training, and filming on that set took them a total of 11 years, and was not without injuries: Hedren, Marshall, and 100-plus members of the crew suffered frequent bites, fractures, blood poisoning, and even gangrene. And that’s without mentioning the severe flooding from a broken dam or the threats from local wildfires.

Once it did lock, miraculously, Roar could secure only international distribution, until a revival placed it in U.S. theaters in 2015. While it can’t trumpet much financial success or tout acclaim, it can take pride (pun intended) in one thing: crediting some of the lions as co-writers.

It’s a great shame that politics disrupted Andrzej Żuławski’s astonishing—and technically unfinished—sci-fi allegory. Having already seen his previous film, The Devil, banned by an increasingly authoritarian Polish government, it wasn’t shocking so much as simply demoralizing to Żuławski when On the Silver Globe was shut down in 1977 due to continued censorship. He abandoned the project, deemed too critical of the regime, and left for Paris.

It took 11 years for Żuławski to return to Poland. When he did, he tracked down all remaining Silver Globe footage and took it straight to the 1988 Cannes Film Festival, filling in narrative gaps with live commentary at the premiere. Digitally remastered in 2016 for New York’s Film Comment festival, the visionary tale of life on the moon was finally seen nearly as Żuławski intended, but it remains elusive on digital platforms.

Perhaps the epitome of a project that never ends is The Other Side of the Wind, Orson Welles’ final feature which began filming in 1970 and was not seen for 48 years.

Even if the film had come out shortly after it wrapped in 1976, the six-year shoot would still rank high on a list of lengthy productions: Principal photography started then stopped multiple times due to large tax bills and an embezzlement scandal (one producer supposedly skipped out with $250,000). But it was after filming that the real time-consuming trouble started: decades of disputes over ownership, sometimes among investors, other times among Welles’ surviving family members after he died in 1985. The sluggishness of these legal conundrums, however, does no justice to the final product: a fast-paced, style-varied experimental drama that persevered and finally landed on Netflix in November 2018.