How was major sci-fi film '10 Cloverfield Lane' made in apparently total secrecy?

The surprise album release has become a staple of the music industry. Beyoncé, David Bowie and Radiohead have all released records without the usual brouhaha, choosing to issue a simple tweet and then let social media and news outlets do the rest.

Initially, the surprise release was a way to combat the pirates, by not giving them any warning that an album was coming. There were other financial advantages: as profits in the music industry plummeted, saving on marketing costs made sense. A by-product of releasing albums this way is that all the focus and talk about the album comes when the songs are available to buy. In our one-click purchase society, there is no delay. The album sales become the story in the subsequent week; the reviews, good or bad, matter less.

Now the film industry seems to have woken up to the surprise release. 10 Cloverfield Lane is a prime example. Success in the movie business is increasingly about box-office returns on the first weekend, so distributors are looking at ways to increase the hype around a product to ensure audiences see a film at the cinema as soon as possible. The old model relied on the idea that hype comes from announcing a movie release as far in advance as possible. That's why there are already more than 30 comic-book films scheduled to come out between now and 2020. Then the trailers come out a year in advance, becoming events in themselves. The final push sees the media only being allowed access to the film in the days before the release. For a film as anticipated as Star Wars: The Force Awakens, that tactic led to front-page reviews on the day of release.

So when JJ Abrams, the director of Star Wars: The Force Awakens, announced that he had produced a sequel to his 2008 hit Cloverfield, there was genuine surprise. When 10 Cloverfield Lane is released on Friday, it will be just two months after the world first learned of its existence. Where, how and when? The idea of a major motion picture being made in secret seems preposterous. For a start, too many people are involved in the making of a film to keep it quiet. In the age of the internet, it is nothing short of a miracle, even from the notoriously secretive director/producer. This was not a small movie being made under the radar; it was a sequel to a hit movie in which fan interest was high.

So how did Abrams do it? Firstly, the script was originally intended for a standalone movie, not a sequel. In 2012, screenwriters Josh Campbell and Matt Stuecken wrote a script called The Cellar, in which a young woman wakes up in a cellar after a car crash and is told by two men who share the bunker that she cannot leave because the world has been attacked by aliens. In that script, the audience does not know if the attack story is true. By putting the film into the alien Cloverfield world, there is an Hitchcockian twist: the audience, but not Michelle (Mary Elizabeth Winstead), knows that the world has been attacked.

When the script was sent to Abrams's company Bad Robot, Abrams saw an opportunity to amend the script and make it a sequel of sorts to Cloverfield, while keeping it on the down-low. Even the actors weren't let in on the ruse. Instead, its stars believed that they were making a movie titled Valencia. They were sent scripts on files that deleted themselves after they had been read. The low budget ($5m) and the first-time director, Dan Trachtenberg, also threw them off the scent. It was only when the trailer was released in January that John Goodman and his fellow actors were told its real title and that it would be part of the Cloverfield universe.

This is not the first movie to have been made in secret. Sacha Baron Cohen has been inventing characters and duping people into appearing with them for years. After years of flops, M Night Shyamalan made the low-budget horror The Visit in secret. And Stanley Kubrick was notoriously guarded about the films he made.

Secrecy is far more prevalent in documentary film-making. Joshua Oppenheimer's Indonesia-set films The Act of Killing and The Look of Silence both had elements of clandestine filming. Originally, the director intended to make the whole film in secret, but his plan went awry when, three weeks after he began, the secret police rounded up all the people he had interviewed and warned them of the consequences. Now working on his next project, Oppenheimer is keeping the story under wraps. “I want to keep the trust of the protagonists in the film,” he says. “If they read something on the internet that I have said and I'm misquoted, unbeknownst to me, then the channel of communication is muddied. So for non-fiction films in the era of the internet, it's dangerous for the director's craft to have lots of stories about what we are doing while the film is being made.”

In all these instances, the public knew of the arrival of the film long before it hit the cinemas. Not 10 Cloverfield Lane. “We're in a moment of instant information,” Abrams told the LA Times of the film's surprise release. “You don't need to prepare people a year in advance to go see a movie. This was all about shaking it up, and this felt like the perfect kind of movie to do that.”

10 Cloverfield Lane is out on Friday