Harry Potter actor Richard Griffiths, who played the grumpy Uncle Vernon, died Thursday from complications following heart surgery. He was 65.
Fellow Harry Potter star Daniel Radcliffe paid tribute to the actor Friday, saying "any room he walked into was made twice as funny and twice as clever just by his presence."
Radcliffe also looked back at his time with Griffiths working on the 2007 Broadway production of Equus.
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"In August 2000, before official production had even begun on Potter, we filmed a shot outside the Dursleys', which was my first ever shot as Harry. I was nervous and he made me feel at ease.
"Seven years later, we embarked on Equus together. It was my first time doing a play but, terrified as I was, his encouragement, tutelage and humor made it a joy."
Griffiths had a long and successful career in film and TV, but also on the stage, where he won a Tony Award for his appearance in The History Boys. He also played a food-loving detective in Pie in the Sky and was well known for his role as Uncle Monty in the cult film Withnail and I.
Artistic director of the National Theatre Nicholas Hytner, who directed The History Boys, said Griffiths' performance in the play was "a masterpiece of wit, delicacy, mischief and desolation, often simultaneously."
Griffiths' Withnail and I costar Richard E. Grant also sent out tweets about the loss of the great actor.
Known for his sense of humor and for shaming audience members in theaters whose cell phones rang during plays, Griffiths last major role on the stage was in last year's West End production of Neil Simon's comedy The Sunshine Boys, opposite Danny DeVito.