Sir Michael Gambon collapsed twice while rehearsing for The Habit Of Art as his crippling memory loss left him struggling to recall his lines.
The 72-year-old British actor has spoken of problems with his memory for the first time in an interview with The Times newspaper, revealing his ill health forced him to pull out of the play at London's National Theatre in 2009.
The actor, who played the role of Professor Dumbledore in the Harry Potter films, confessed his memory had become so bad he had to be whisked away in an ambulance during rehearsals.
He says, "I think it's linked to the memory. It was a really major, big part. I've never told anyone this before. I think I got so frightened that I collapsed. They did all sorts of tests on me and they couldn't find a thing... I then recovered, so we started rehearsals again and I collapsed again. So the ambulance took be back to St Thomas' (Hospital in London). It's rather sad.
"And then they recast it. I couldn't do it. That is linked with what is wrong with me. It was overwhelming fear. And I am not exaggerating or lying, the two fast journeys to the hospital, I was completely out, I was gone, I was on a drip, everything."
Gambon has now landed a role in a short play entitled Eh Joe - and the part has no lines to remember. He adds, "I'm getting so old now, so it's like a dream being offered this part."