With Chris Hemsworth and Tessa Thompson stepping up as the new leads in Sony's Men in Black: International, the sci-fi franchise has entered a whole new era of peacekeeping against alien threats, taking the agency's initiative all over the globe. However, this premise and change and cast wasn't always the plan for the popular film series' fourth installment. Instead, a more traditional sequel featuring the return of longtime leads, Will Smith and Tommy Lee Jones, was the studio's first choice, rather than a total reinvention of the franchise.

With the Men in Black series seemingly reinvigorated by 2012's Men in Black III, filmmaker Barry Sonnenfeld, along with Smith and Jones, all seemed open to the possibility of returning for a potential direct sequel. Sonnenfeld had even suggested to Smith about having the actor's son Jaden join him in a proposed follow-up, with Smith reluctant to pass on the franchise to a new set of stars. With the three longtime collaborators enjoying their experience making the third film in the original trilogy, Smith and Jones appeared poised to reprise their iconic roles at least once more.

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Men in Black III would prove a runaway success for Sony, earning $624 million at the worldwide box office -- the highest earning entry in the franchise to date. Confident in its future with its original stars, Sony commissioned Oren Uziel in May 2013 to write the screenplay for a planned sequel to Men in Black III after the screenwriter's previous success penning 21 Jump Street for the studio. While Smith appeared noncommittal at the time of Uziel's signing, Jones appeared to still be on board to return to his no-nonsense role as veteran operative, Agent K.

The proposed sequel hit a major snag the following month as Smith indicated he was done with the franchise, claiming to be tentatively open to considering a return but feeling ready to pass on the sci-fi film series to someone else. The fan-favorite actor had launched his cinematic career with the first installment in 1997, even providing a hit rap song for the film's soundtrack. With its original star apparently out, Sony quietly shelved its plans for a direct sequel while it rethought the franchise's future.

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Instead of a traditional sequel, Sony decided to cross over Men in Black with its other, more grounded comedic success, 21 Jump Street. Initially revealed by leaked internal emails after Sony was publicly hacked in December 2014, Sony planned a spinoff installment crossing over the two comedic franchises, with star Jonah Hill emailing Sony studio executive Amy Pascal his enthusiasm for the potential project. Will Smith and Tommy Lee Jones were not expected to reprise their roles for the crossover but the agency itself would figure prominently.

Even after the leaks, Sony still planned to move forward with the project, with a script written by Rodney Rothman while James Bobin entered talks to direct the crossover in March 2016. Original directors Phil Lord and Chris Miller remained attached as producers while tentatively beginning work on Solo: A Star Wars Story before their own departure from that project. Despite the reported progress and voicing his earlier support, Hill would later remark that he doubted a crossover film between the two franchises would actually be produced, a stance that eventually proved to be prophetic.

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With the crossover also shelved by Sony, the studio decided to reinvent the franchise is a soft reboot that would better position it for global audiences. Sony planned a revival trilogy of films with new leads and signed director F. Gary Gray after fast-tracking a script written by Matt Holloway and Art Marcum in 2017. Chris Hemsworth began talks to star as the new lead in February 2018 with Thor: Ragnarok co-star, Tessa Thompson, signing on to reunite with him on screen the following month. With its new leads and crew assembled, principal photography on Men in Black: International began July 2018 and lasted until that October.

Men in Black International

For five years, Sony struggled with a new way to proceed with the Men in Black franchise after the loss of original lead actor, Will Smith. What had begun as a straightforward sequel led to plans for an unlikely crossover before a soft reboot with new leads was ultimately settled on as the way to move forward. The ephemeral, changing plans for a fourth Men in Black film illustrates a studio that wanted to keep a cinematic franchise viable without necessarily knowing exactly what they wanted to do with it. An indecisiveness reflected, perhaps, by this latest iteration's poor reception and projected financial losses.

Directed by F. Gary Gray, Men in Black: International stars Chris Hemsworth, Tessa Thompson, Rebecca Ferguson, Kumail Nanjiani, Rafe Spall, Laurent Bourgeois and Larry Bourgeois, with Emma Thompson and Liam Neeson.