Rhys Ifans confessed he was "totally freaked out" seeing himself as a giant lizard in The Amazing Spider-Man.
The Notting Hill star appears opposite Andrew Garfield in the new superhero, comic book blockbuster as Dr Curt Connors, a scientist who becomes mutant villain The Lizard.
Rhys said: "I've never seen a film in 3D before, from beginning to end, so seeing yourself in 3D, 25 foot high, is spooky."
The Welsh actor, who attended the premiere of the film in London's Leicester Square with his girlfriend Anna Friel, revealed Dr Connors is not all bad.
Rhys said: "He's a great man, he's compassionate, soulful, fragile and he wants to heal himself and heal the world. He just has a bad day at the office and it goes badly wrong."
As for whether he will return in the sequel Rhys said: "Who knows? You shouldn't ask me that. I'm just the dancing girl."
The Amazing Spider-Man opens in cinemas on July 3.