Hudson, who played Winston Zeddemore in the first two Ghostbusters movies, said the new film can still work without Harold Ramis, who died in 2014.
"We miss Harold, because Harold was really the glue that I think held everybody together," Hudson told The Daily Mail. "He was always my go-to point and anything that was a little bit weird, or whatever, Harold was the guy who would sort of say, 'Ernie, just…' and explain the world to me."
Hudson said everyone misses Ramis, co-wrote the first two films with Aykroyd, but his "spirit is there."
"[Director] Ivan Reitman is there and everybody is in," Hudson told the Daily Mail. "Now whether the studio will do it, I'm the guy who sits by the phone and waits for the call. So if they call, I'll answer. If not, I've got other stuff that I'm doing."
Hudson said Murray and Aykroyd still have enough left in the tank to make fans of the original films happy.
"I think we do. We've grown, we've learned and a lot of really new young talent that I'm sure they'd bring in to it. So it would be a lot of fun. I think it would only deepen. And we'll miss Harold," he said.
Hudson also said he "enjoyed" the 2016 Ghostbusters, which starred Melissa McCarthy, Leslie Jones, Kristen Wiig and Kate McKinnon as a new group of Ghostbusters. The actor made a cameo in that film, so he made sure not to throw shade at the movie.
"No disrespect to [director] Paul Feig and I enjoyed working with him, but I just think it was different," he said.
Back on Jan. 15, Sony Pictures surprised fans by announcing that filmmaker Jason Reitman, the son of Ivan Reitman and director of Juno and Up In The Air, will write and direct a new Ghostbusters film. Sony even released a brief teaser showing the famous ECTO-1 car and setting 2020 as the film's release date.
The new film is expected to ignore the events of the 2016 Ghostbusters, and will instead follow 1989's Ghostbusters II.
"I've always thought of myself as the first Ghostbusters fan, when I was a 6-year-old visiting the set. I wanted to make a movie for all the other fans," Reitman said this week. "This is the next chapter in the original franchise. It is not a reboot. What happened in the '80s happened in the '80s, and this is set in the present day."
Sony has not formally announced the cast, but Aykroyd and Hudson both showed their support on Twitter after the teaser was unveiled.
"If you need a tune-up, you know who to call," Aykroyd wrote.
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