Bryan Cranston reveals why Erik Per Sullivan rejected 'buckets of money' for Malcom In The Middle reunion

The Malcom In The Middle cast have reunited for a limited series, 20 years after we last saw them on screen together back in 2006 - but one key character is missing.

Fans can barely contain their excitement over the four-episode revival, titled Malcolm In The Middle: Life's Still Unfair, which brings together the chaotic family once more.

Bryan Cranston returns as Hal, Frankie Muniz as the titular character, and Jane Kaczmarek as Lois for the TV show, with all episodes set to premiere on 10 April on Hulu and Disney+.

After shielding himself and his daughter from his family for more than a decade, the reunion sees Malcolm get dragged back into their orbit when Hal and Lois demand his presence at their 40th anniversary party.

But as mentioned, there's one key actor who won't be appearing in the long-awaited revival - Erik Per Sullivan, who played the family's youngest son and Malcolm's little brother Dewey in the sitcom.

Erik Per Sullivan is the only Malcom In The Middle actor who's been recast (Jim Spellman/WireImage)

And apparently, the 34-year-old turned down a big payday by not returning and allowing the role to be recast, with Caleb Ellsworth taking on the part instead.

Sullivan has stepped away from the world of acting and is currently studying for a master’s degree in literature at Harvard University, meaning he couldn't commit to the role.

In a new interview with The Guardian, Kaczmarek explained: "He’s studying Dickens and is an incredible student – they offered him buckets of money to come back, and he just said: ‘No thank you’".

Meanwhile, Cranston told Variety: “It wasn’t like, ‘I can’t.’ It was like, ‘I’m different. I’m not the child actor that I was. I’m an adult. I’m into academia, and I’m studying, and I love that world. And it’s like, ‘Yeah, good.’”

He really has stepped out of the limelight as he currently has no public social media accounts and as per MailOnline, hasn't been on TV screens since appearing in the 2010 crime thriller Twelve.

In the Guardian interview, Muniz, who plays the lead role of Malcolm, talked about the unprecedented levels of fame the original show brought him.

Cranston recalled what Sullivan said when asked if he would join the reboot (Theo Wargo/Getty Images)

He recalled: “One of the wildest was the first time I went overseas. I had no idea people knew the show there. I was in Geneva, walking with my girlfriend, and people were looking. By the end of it, we were literally being chased down the street.

"When I’m in Europe, or I’m in Mexico or in Central America, people love the show so much that … I’m not comparing myself to the Beatles at all, but it almost was that odd level of ‘What is happening?’”

And touching on how the reboot came to be, he added: "I had dinner with Bryan, and I remember him saying something like: ‘There’s no role I’d want to revisit more than Hal,’ so he took the lead. It’s thanks to Bryan that it really did happen."

You can watch Malcolm in the Middle: Life's Still Unfair from 10 April on Hulu and Disney+