With the countdown on for Steven Spielberg‘s Disclosure Day, Josh O’Connor has had to keep the details of the script top-secret.

The Golden Globe winner recently revealed the lengths Spielberg took in order not to let any of the David Koepp-penned screenplay leak before it premieres June 12 in theaters, recalling how he first received the pages while shooting Wake Up Dead Man: A Knives Out Mystery in the UK.

“There was, of course, a level of secrecy. When I received the script I was filming Knives Out and I was in a hotel and a motorbike turned up with the script, and a motorbike turned up to take away the script the next morning,” he recounted to the Associated Press. “That’s the first time that’s happened for me.”

O’Connor added, “It’s a very strange experience but it makes sense. You know, anytime you hear that Steven’s got a film coming out, everyone, myself included, wants to know what it is, so I totally understand why.”

Although the plot of Disclosure Day has largely been kept under wraps, the sci-fi thriller stars O’Connor as Daniel, a cyber security expert with access to long-held government secrets about extraterrestrial life and plans to become a whistleblower.

Having previously explored explored life on other planets in Close Encounters of the Third Kind (1977) and E.T. the Extra-Terrestrial (1982), Spielberg explained this month at CinemaCon why he remains so intrigued by the topic.

“It’s entirely shrouded in mystery,” he told Disclosure Day‘s Colman Domingo. “There are those who know exactly what is happening in our skies [and] this movie will cause you to ask a lot of questions.”

Spielberg added, “This is a movie that needs to be experienced, and what you need to get from the beginning to the end is a seatbelt.”