Also joining the Zoom: director Ivan Reitman and his son, Jason Reitman, who directed the upcoming 2021 sequel "Ghostbusters: Afterlife." Sadly absent was Harold Ramis, who passed away in 2014.
The Reitmans were the first to hop on the call, before they got Bill, Dan, Ernie, Sigourney and Annie on the line. And, yes, Murray was wearing a sailor's cap, as an homage to the Stay Puft Marshmallow Man.
Ivan Reitman first talked about Sigourney's audition to play Dana, which he said "blew my socks off." Recalling the audition, she said, "I had to become a dog and I was really willing to become a dog for the whole show. I kept howling, growing." According to Ivan, Dana's transformation was actually Weaver's idea.
"You said, 'I really think I should become possessed and become a dog myself,'" he recalled. "That's really where that came from."
Murray said he signed on after reading about 27 pages from Dan's first draft. "I thought, 'This is the best thing I've seen,'" he said, "I called him back and said, 'I'm in.'" Murray also revealed the then-mayor of NYC Ed Koch did not "like us at all" at the time.
He specifically remembered a cast Thanksgiving dinner during production, where he showed them an early cut of the ballroom scene with Slimer. "He showed us those scenes without all the special effects and from that moment on, I went back to work saying, 'Guys, let's all calm down, it's gonna be really big,'" he said.
Aykroyd said that "80%" of what ended up on the screen was improv. "When you bring a master comedian and charismatic leading man like Bill Murray into a project, you know there's gonna be contributions on the writing side," he explained.
Reitman admitted the aspect of the film he was "most afraid of" was the Stay Puft Marshmallow Man, which was in Dan's original script. "I thought, the audience will go with us all the way, I'm not so sure they're gonna go for that 80-foot marshmallow man," he added.
The group then all opened up about working with Harold Ramis. Reitman considered him a "brother figure," Aykroyd then praised him as an incredible writing collaborator -- one who did not believe in ghosts himself. Hudson celebrated his work ethic, while Murray praised his calmness on the movie, which he said was "very hard to make."
As talked turned to Rick Moranis, Reitman revealed John Candy was actually originally approached to play the role of Louis Tully. "He didn't really get it," said Reitman, "He kept wanting to play him with a German accent, with a couple of German Shepherd dogs. I said, 'I think that would be confusing given the dogs that are already on the roof.'"
"Rick read it and called me immediately and said, 'John just made a terrible mistake, I'm so happy,'" he added.
While Moranis -- who stepped out of the spotlight in 1997 following the death of his wife -- didn't join the call, William Atherton -- who played odious Walter Peck -- popped up and revealed that, thankfully, nobody has ever came up to him in public to tell him, "That man has no dick."
The group was then joined by super-fan Kumail Nanjiani, as Aykroyd asked the now-buff star to take his shirt off. Sadly, he didn't, but he did do a few memorable line readings with the cast.
Gad also had a few memorable supporting actors pop up, as Venkman's test subjects, the movie's hotel manager and the man who played Dana's violinist boyfriend, Timothy Carhart, got the spotlight.
The stars also revealed what they believe the secret to the franchise's success really is. "It's packed full of heart and good feeling and kindness and everyone loves ghosts to start with," said Aykroyd, who also praised the incredible cast and director.
"It doesn't matter whether you're young or old, the film crosses generations," added Hudson.
Before closing, there was one final surprise from Ray Parker Jr., who joined to sing the movie's iconic theme song. He revealed all Reitman told him was that he needed to get "Ghostbusters" into the lyrics, something he admitted just "does not sing well." Thankfully, he was inspired by the guys' commercial in the film and the rest is history.
After a COVID-19 delay, Jason Reitman's "Ghostbusters: Afterlife" is set to hit theaters March 5, 2021.