One of the biggest "what ifs" of the last few years is the hugely anticipated 21 Jump Street slash Men in Black crossover, given the confirmed title of MIB 23 in the same conference Spider-Man: Homecoming was announced back in April 2016. James Bobin, known for his work on 2013's The Muppets, was attached to direct not long afterwards — but sadly, the film has sat in development hell ever since, with conflicting reports whether the project could ever get off the ground.

We had the opportunity to speak with both Channing Tatum, star of the Jump Street franchise, and Magic Mike writer Reid Carolin ahead of Dog, their co-directorial debut releasing later this month. When we told him of our disappointment about the crossover not going ahead, Tatum didn't hold back, concurring absolutely that he wanted it to happen — and that, in fact, he still thinks it could. "You're preaching to the choir, man," he told Collider's Steve Weintraub, "I still think it could work, I really do," implying it could still happen if Sony work out the difficulties:

"You're preaching to the choir, man. I still think it could work, I really do. And if Sony would ever really, like, I think do the hard work and figure out the producer problems that are inherent with that film, I think we can still do it. But right now, I don't know why, they're just not motivated to do it. It's a big overhead on that movie, so."

21-jump-street
Image via Columbia Pictures

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More tantalizingly, Tatum described MIB 23 as "by and away the best third sequel to any franchise that I've ever read, in my entire life," with which Carolin agreed. "Oh, funniest script — one of the funniest scripts I've ever read," he said. "Bar none," Tatum followed, "and I would not say that if I did not really believe it, because I don't like being wrong, like, specifically about that".

So: great script, a hot Hollywood lead ready and primed to go ahead with it, two of the biggest movie franchises in recent history... a formula for guaranteed success, you'd think. So what's the hold up?

Well, there are a lot of producer contracts that need to be re-negotiated before production on the film can even be touched. "There's [Steven] Spielberg, Neil Moritz, and Walter Parks," Tatum said. "They're giant producers, y'know, on that. And then once everybody is kinda like, not willing to come off their fee, you end up having a producer fee that is essentially, maybe more than the actual budget on the movie," he explained.

But what is a producer contract, and why is it such a hold up here? Here's the long and short: every producer gets a fee when a movie is made, and some old contracts — like Men in Black — were written so that a producer may get first dollar gross, or greater control. When you combine franchises, producer deals need to be worked out so they get paid, but also so that the budget is something the studio still feels they can make a profit on.

Will Smith and Tommy Lee Jones holding guns in Men in Black
Image via Columbia Pictures

We'll never know the specifics of Hollywood contracts, but the ones set up on Men in Black might be a lot different from the contracts of the past few years. So, to make this movie, all the producers attached to both properties have to agree to new deals. It's a huge headache. But come on, Sony, Tatum's right: make it happen!

Watch what Tatum and Carolin had to say in the player above, and keep an eye out for our full interview for Dog, coming soon to Collider. For more on the Men in Black/Jump Street crossover movie, here’s Chris Miller and Phil Lord talking about the film.