Kevin Smith Says Near-Fatal Heart Attack That Inspired Clerks III Was 'Greatest Gift I Ever Had'

John Bayer/Lionsgate

Kevin Smith survived a brush with death in his journey back to the Clerks movie universe.

"That heart attack was the greatest gift I ever had," Smith, 52, tells PEOPLE of the massive heart attack he suffered in 2018. "Not only did it save my life, make me go vegan and go healthier and stuff, but it gave me the spine for Clerks III."

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"And because of that, it winds up being this personal journey in a way that no Clerks movie should be ... The guy who started making these movies couldn't have predicted this," Smith adds.

It all began with Clerks in 1994, his black-and-white directorial debut about a day in the life of convenience store clerk Dante Hicks (Brian O'Halloran) and his best friend Randal Graves (Jeff Anderson).

Courtesy of Lionsgate

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The critically-acclaimed indie hit was largely inspired by Smith's job at the very same store where he made the movie with film school classmate and co-producer Scott Mosier.

Smith recalls that he originally "killed the main character at the end of that movie," adding: "And then we wound up cutting that and suddenly it opened it up for 'Oh, I guess I could go back to the Quick Stop if I wanted to.'"

"So whenever I go back, it recharges my batteries. As a director, as a filmmaker, storyteller, I have found that going back really unearths the best in me, for lack of a better description, the poet in me," he explains. "I've made a lot of flicks, but honestly, the best three have the word Clerks in the title. So the boys, Dante and Randal, bring out the best in me."

Clerks III is heavily influenced by his "Widow-Maker" heart attack, which Randal also suffers in the film.

Courtesy of Lionsgate

One such autobiographical scene features Randal on an operating table during the health scare as the theme song of Degrassi: The Next Generation begins playing in his head. "That was based on real life," Smith notes.

"I was making peace with the fact that this could be it," he recounts of when the doctor told him he had an 80 percent chance of dying. "And so at one point I started singing what I feel is one of the most positively reinforcing songs ever recorded, which is the opening theme song."

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Smith and Jason Mewes previously played versions of themselves on the popular spin-off of the 1980s Canadian teen soap with arcs in 2005 and 2009. "Now, here I am dying of a heart attack, so that song became even more profound for me," he adds.

Whereas the first Clerks drew from life in his early 20s, 2006's Clerks II took inspiration from his 30s and the third installment represents Smith's 40s and beyond.

"And certainly the end is part of that. When you're my age, you start thinking, 'Wow. Mathematically speaking, there's definitely got to be less time in front of me than behind me,'" Smith muses. "And I remember working in that store and having all the time in the world, all the time scheming and dreaming."

Courtesy of Lionsgate

Smith has since garnered a massive loyal following with the film franchise that includes Mallrats (1995), Chasing Amy (1997), Dogma (1999) and Jay and Silent Bob Strike Back (2001), the titular characters of which (played by Mewes, 48, and Smith) link all the films.

In recent years, he's rolled out a new phase of the View Askewniverse (named for his and Mosier's production company), including 2019's Jay and Silent Bob Reboot and a planned Mallrats sequel.

Kevin has also made his films a family affair, ever since his mother Grace Smith played the Milk Maid in the first Clerks film. He initiated wife Jennifer Schwalbach Smith into the franchise as well with Strike Back, which also featured their daughter Harley Quinn Smith as a baby.

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"And here she is, age 23, still in these. She can't escape Kevin Smith pictures," he says of Harley, who previously appeared in Quentin Tarantino's Once Upon a Time... in Hollywood.

All three of the Smith women return for Clerks III, carrying on a beloved family tradition and giving Kevin's legacy a personal touch.

"You're lucky if you get to make films, and you're way luckier if somebody else pays for them. But you got to use them as little snapshots of your life. I've charted my kids' growth throughout these movies," Smith raves.

Lionsgate in partnership with Fathom Events will be releasing Clerks III exclusively in theaters from September 13-18.