Very little is known about Avengers 4, as Marvel are going out of their way to keep spoilers secret.
Fans are worried that major characters like Iron Man or Captain America could be killed off for good.
So it should come as no surprise that Marvel Studios have adopted some pretty extreme methods to prevent leaks.
Nebula star Karen Gillan revealed just what the actors had to go through to Shoot This Now podcast.
Speaking with Hey U Guys, he said: “The secrecy around this film extended, this time, to the cast. I mean, really, it was crazy.
“We read scripts that were fake scripts and then they had fake twists and scenes that never were shot and you’d talk to the director and they’d say ‘all of that stuff at the end? Not happening.’”
According to Movie Web, Spider-Man star Tom Holland has said something very similar.
In a previous interview he said: “When I read the script, there were fake scenes in it.”
Holland continued: “I got the directors on the phone and they walked me through what were the fake scenes.”
“They’d had three leaks already, so they’d written a script with lots of fake scenes.
“There were three Hero iPads that had the only real scripts on them.”
Avengers 4 will be released in UK cinemas on April 26, 2019.