Scarlett Johansson, Channing Tatum, Greg Berlanti and more of the Fly Me to the Moon team celebrated their upcoming film at its New York City premiere on Monday night.

The rom-com follows Johansson’s Kelly Jones, a marketing executive hired to “sell the moon” to America ahead of the Apollo 11 moon landing. When she makes her way to Cape Canaveral, Florida, to work her marketing magic, she wreaks havoc on launch director Cole Davis’ (Tatum) already difficult task of preparing for the space trip.

When the White House deems the moon landing too important to fail, she receives an order to stage a fake moon landing as a backup, in case things don’t go smoothly for Neil Armstrong (Nick Dillenburg), Michael Collins (Christian Zuber) and Buzz Aldrin (Colin Woodell).

While Fly Me to the Moon is a fictional story, the premise of the film is based on an actual conspiracy theory that the moon landing was faked, and that theory was front of mind for the project’s cast and crew.

“I think the fact that NASA was always going to participate in this movie to the degree that they did always made me know that we were honoring actually what happened,” Berlanti told The Hollywood Reporter at the premiere. “When you see the movie, without giving away the ending, you realize that so much of it is about why the truth is important. And so I think I was fine to take on an OG conspiracy theory, knowing that in the end, what we were really trying to say why the truth matters.”

The director also served as a producer alongside Johansson, who brought the project to life with her These Pictures banner. For the Avengers star, it was interesting to be able to play with that conspiracy theory in the film and the idea that there was an alternate plan.

“Just playing around with that idea, like throwing the ball around creatively, and then, of course, Rose Gilroy coming in to write the script, that was like the missing piece,” Johansson told reporters on the carpet. “She’s such a playful writer. … She got the tone immediately. The script was undeniably great.”

Ultimately, the film is about a team of people who team up to make sure the moon landing isn’t fake, explains star Jim Rash. “However, the idea that sure, the government had a backup plan — probably,” he told THR. “So it was an interesting twist on that idea.”

Despite Fly Me to the Moon being purely fictional, Berlanti noted they used a tremendous amount of NASA’s archival footage that had never been seen before, which was inspirational for them. There was also a NASA historian on set, whose job it was to protect the integrity of the space program and the real-life people featured.

Nick Dillenburg, who portrays Neil Armstrong in the film, recalled an original line in which he said “I gotta go take a leak.” That was something the historian on set pushed back on because they wanted to protect the famous astronaut’s image and “not talk about him going to the bathroom.”

As for why Johansson and Tatum were the ideal stars to take on the lead roles in the film, Berlanti shared that they really encapsulate “the spirit of the movie.”

“Their innate goodness, their innate comedy, drama, charm, it makes you want to watch them and want to watch the story,” he said. “They’re funny, and they’re smart, and hopefully, the movie is those things too.”

Fly Me to the Moon hit theaters July 12.