For the record, Dan Aykroyd really does believe in ghosts. “It’s the family business, for God’s sake,” he says from his family’s farmhouse in Ontario, site of Aykroyd séances for generations. Aykroyd’s great-grandfather was a renowned spiritualist; the family had its own regular medium to channel souls from the other side. His grandfather—a telephone engineer—investigated the possibility of contacting the dead via radio technology. His father authored a well-regarded history of ghosts; strange lights halo his daughter in photographs.

Yet Aykroyd was the first to turn the supernatural into a highly lucrative global franchise. Drawing on his spectral heritage, Aykroyd sat down one day and started writing Ghostbusters. The finished result catapulted a crew of already-famous Saturday Night Live and Second City comedians to international superstardom, and became a watershed in the industry, eroding the once insurmountable barrier between television and film actors. “Ghostbusters—one of Columbia’s most iconic films of all time—[also] basically invented the genre of special effects-driven comedy,” says Doug Belgrad, president of Columbia Pictures.

While taking a place of honor among the pantheon of historical comedy-horror films, Ghostbusters would also inspire subsequent generations of comedians to get into the game. “It really is a perfect comedy,” says Judd Apatow. “It was all those people at the height of their powers; they had mastered their craft . . . [and] made the [film] we dreamed they’d make. Movies like Ghostbusters . . . made us want to make movies.”

Yet Ghostbusters’s astronomical success was far from a foregone conclusion: from its inception, the eventual blockbuster faced countless obstacles, unravelings, and emergencies. The film’s budget scandalized and divided its studio executives, who considered the project a “horrendous[ly]” expensive risk to be carried on the backs of former television actors and a relatively inexperienced director. “This was not Animal House or Caddyshack or Stripes,” recalls Tom Shales, veteran television critic and co-author of Live from New York: An Uncensored History of Saturday Night Live. “Those were all little movies. This was a big, big gamble.”

One of the leads for whom the script was written unceremoniously died of a drug overdose. The screenplay called for scores of special effects, and the major effects operations in town were tied up with other projects. To top it off, the Ghostbusters team was given a mere year to re-write, shoot, and edit the movie—even though none of the principals had ever attempted a project of that scale before. “The wisdom in town was that I had made a terrible mistake,” says former Columbia chairman Frank Price, who greenlighted the project.

Decades later, drama continues to surround the Ghostbusters enterprise, which has seen both spectacular triumph and wilting disappointment. Despite press reports of infighting among Aykroyd, Bill Murray, and Harold Ramis (who died earlier this year), the stars of the first two Ghostbusters films, Columbia Pictures has confirmed that a long-rumored Ghostbusters III is in development. On the eve of the 30th anniversary of the original 1984 Ghostbusters, its cast, director, producers, and other industry greats share their recollections about the genesis of the Ghostbusters phenomenon, and talk about its legacy and the future of the franchise.

“The Mount Vesuvius of original ideas.”

It would be impossible to write about Ghostbusters without first writing about Saturday Night Live: in many ways, S.N.L. was the Zeus from whose head Athena later sprang. “Even though [Saturday Night Live creator and executive producer] Lorne Michaels had nothing to do with Ghostbusters, the movie was a tribute to those first five years of S.N.L. and the revolution it represented,” says Tom Shales. Upon its 1975 debut, S.N.L. immediately established itself as a major cultural phenomenon. Lorne Michaels’s ambitions for his new show were unabashedly outsize: “We wanted to redefine comedy the way the Beatles redefined what being a pop star was,” he later said in Shales’s book Live From New York: An Uncensored History Of Saturday Night Live.