'That movie has not been fully nailed': Paul Walter Hauser had doubts about joining The Fantastic Four cast

Paul Walter Hauser was hesitant to join the cast of 'The Fantastic Four' after the poor performance of previous movie adaptations.

The 37-year-old star will play an undisclosed role in the upcoming Marvel Cinematic Universe (MCU) picture and confessed that he had a sense of unease about the project as previous movies – including the disastrous 2015 film – have flattered to deceive.

Speaking to The Hollywood Reporter, Paul said: "Don't think that didn't weigh in as I was deciding whether or not take the job. That movie has not been fully nailed just yet.

"But I really do think the combination of the screenplay, and the department heads that are working on the film, and that classy cast of really exciting actors – some of them known for a long time, and some of them having a moment right now – (make me feel that) this movie is special, and it was something I wanted to be a part of."

Paul revealed that he was persuaded to join the project after discussing it with director Matt Shakman over dinner.

The 'Cruella' actor said: "Matt Shakman directed me years ago in 'It's Always Sunny in Philadelphia'. To come back together and collaborate on this movie in some capacity, it's really exciting. I'm excited to be part of the Marvel Cinematic Universe."

Joseph Quinn is also appearing in the film as superhero Johnny Storm/Human Torch and recently dismissed fears that superhero fatigue could hinder the project's performance at the box office.

In an interview with Entertainment Weekly, Joseph said: "I think that with the story of the Fantastic Four, it feels like we want to get this right.

"There are aspects of it that are very different to other Marvel films. That felt very compelling to me. And again, going back to who's involved, Matt, of course, the director, I think is brilliant, and the cast, and I've read it and the script is brilliant. It's really brilliant. I'm delighted to have this opportunity."

The 'Stranger Things' actor continued: "Superhero movies are movies about people. And if we're invested in the people and the characters and the peril and the spectacle, then that's why people go to the theatres to watch films. We're not just in a penny; we're in for a pound with this one. We're going to go for it."