But the actor/director/writer told Access Hollywood the movie – which is slated to introduce a whole new generation of Ghostbusters – will only be made if the script is good.
"There's a story that I wrote with my co-writer's on this film, Lee Eisenberg and Gene Stupnitsky. The studio has commissioned the screenplay," Harold recently told Access while promoting his new comedy "Year One." "All the principals (himself, Sigourney Weaver, Bill Murray, Harold Ramis and Ernie Hudson) have said they're in, if we get a good screenplay."
Though a script is in the works, a movie in the theaters is not a sure thing. Harold wants the third movie to live up to its predecessors.
"But, we're all reserving judgment," he continued. "There's no reason to do it if it's not good."
And though Dan Aykroyd recently said that he hopes stars such as Alyssa Milano and Eliza Dushku sign on to join the ghost-fighting team's second-generation squad, Harold said casting is a long way off.
"We want to introduce new Ghostbusters," he explained. "I think [Dan] was just throwing out examples of the kind of people who could be in the film."
Adding, "Hopefully the story will feel enough like the old one to revive and sustain people's interests, but new enough to deliver some surprises."
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