'Chernobyl' and 'Harry Potter' actor Paul Ritter dies at 54

His agent said he had been suffering from a brain tumour

Versatile British actor Paul Ritter, whose roles ranged from a hapless suburban patriarch in sitcom Friday Night Dinner to a Soviet engineer who helps to cause a nuclear disaster in Chernobyl, has died, his agent said on Tuesday.

He was 54 and had been suffering from a brain tumour.

A familiar face to British television viewers and theatregoers, Ritter played Martin Goodman, the eccentric father of a London Jewish family, in the acerbic but warm Channel 4 sitcom Friday Night Dinner.

He also played ill-fated nuclear engineer Anatoly Dyatlov in the Emmy-winning HBO drama Chernobyl; the wizard Eldred Worple in Harry Potter and The Half-Blood Prince; and a devious political operative in the James Bond film Quantum of Solace.

Those who worked with Ritter in his most famous roles rated him highly. Robert Popper, creator of Friday Night Dinner, said Ritter "was a lovely, wonderful human being. Kind, funny, super-caring and the greatest actor I ever worked with".

Chernobyl screenwriter Craig Mazin said on Twitter that Ritter was "one of the most gentle, gracious and brilliant people I've ever known, much less worked with. We lost him today, and far too soon. I wish his family and loved ones peace and comfort as they mourn the passing of this beautiful man".

Ritter was a compelling stage actor, a frequent and memorable cast member in productions at Britain's National Theatre, including All My Sons, Coram Boy and The Curious Incident of the Dog in the Night-Time. He also appeared in Art at London's Old Vic and on the West End stage as prime minister John Major, performing opposite Helen Mirren's Queen Elizabeth II in royal drama The Audience.

The actor was nominated for a Tony Award in 2009 for his performance in Alan Ayckbourn's farce The Norman Conquests on Broadway.

Actor Russell Tovey said Ritter was “one of the nicest and best actors you’ll ever meet".

Actor-comedian Rob Delaney tweeted that Ritter had "knocked it out of the park in Chernobyl. Watching it I consciously thought, 'Oh, we have a new movie star.' Between that and how funny he was in Friday Night Dinner … just unreal talent".

Agency Markham, Froggatt & Irwin said Ritter died on Monday night “peacefully at home with his wife Polly and sons Frank and Noah by his side".

“Paul was an exceptionally talented actor playing an enormous variety of roles on stage and screen with extraordinary skill,” the agency said. “He was fiercely intelligent, kind and very funny. We will miss him greatly.”