On March 30, 1990, four anthropomorphic reptiles named Donatello, Leonardo, Michelangelo, and Raphael made their movie debut. By then, Teenage Mutant Ninja Turtles was a cultural phenomenon. Beginning in 1984 as an independent comic book, the Turtles had since grown into far more than that: multiple comics, an animated TV show, a Dungeons & Dragons–esque role-playing game, and a bestselling toy line.

But neither the existence nor the success of a live-action adaptation was preordained. It’s nearly impossible to fathom now, but there was a time when Hollywood did not stockpile pre-existing intellectual property. For a stretch, no one seemed to be interested in bringing franchise cocreators Kevin Eastman and Peter Laird’s brainchild to the big screen. Up until the late ’80s, the most serious interest Eastman and Laird had received was from B-movie king Roger Corman, who wanted to enlist comedians to play the title roles. “Sam Kinison, and Gallagher, and Billy Crystal, and Bobcat Goldthwait, wearing sort of green paint and shells and being the Turtle characters,” Eastman recalls. “It was a very hilarious treatment and concept.” Thankfully, that one never got made.

But eventually, Hong Kong’s Golden Harvest did agree to finance TMNT. But the production was a quagmire: The budget was low, there was infighting among the filmmakers, the cutting-edge animatronics developed by Jim Henson’s Creature Shop to power the Turtle costumes often broke down, and the young cast’s tolerance for physical and mental exhaustion was tested daily. Still, a mixture of technical wizardry, a clever director who cut his teeth making classic music videos, and a group of indefatigable actors saved Ninja Turtles from being a typical kids’ schlockfest—and that translated at the box office. Besides the movie being far better than anything about amphibious superheroes named for Italian Renaissance artists had any right to be, it also became a massive hit, pulling in more than $200 million worldwide and grossing the fourth-most money out of any movie in 1990.

“If you added up everything that could go wrong, it did go wrong,” says Tom Gray, then Golden Harvest’s head of production, “but the result of the baby was beautiful.”

[Read Alan Siegel's oral history of Teenage Mutant Ninja Turtles.]