Speaking at the world premiere of Harry Potter and the Deathly Hallows: Part 2 in London, the Neville Longbottom actor told Digital Spy that he was "absolutely terrified" of filming a dramatic showdown between the unlikely hero and Voldemort.
"I was terrified, absolutely terrified. Ralph [Fiennes] is such an amazing actor," Lewis recalled. "He's a god in the world of acting. I didn't know how to approach it. We did a little bit of a run through with the lines and, I don't even know if he is aware of this or did it on purpose, but he just stared at me - he never took his eyes off me.
"He was studying my face and I was so frightened. We then went straight into the scene and all that fear in my face was because I was genuinely frightened. It suddenly becomes tunnel vision - it's you and Ralph, and you have to do the best you can. I've no idea if it's any good, I don't know, but I loved every minute of it."
> Read our recent interview with Matthew Lewis
Taking in the huge number of fans who filled Trafalgar Square to greet the film's stars, the actor admitted: "You never get used to a Harry Potter premiere; it's impossible to get used to it.
"This is something else entirely, and I think I've suddenly realised that this is the last one - this is the last time we will be in Leicester or Trafalgar Square for a Potter premiere. These fans are the best in the world."
Additional reporting by Simon Reynolds.
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