LONDON: British actress Helen Mirren had no trouble transforming herself from monarch to menacing creature for the new "Monsters, Inc." animated movie, but said she's not so frightening in real life.

The 67-year-old veteran of stage and screen made headlines last month when she stormed out of a London theatre dressed as Queen Elizabeth to berate a group of drummers playing noisily outside in an expletive-riddled tirade. She later apologized.

However the actress, who lends her voice to the terrifying winged monster heading the School of Scaring in "Monsters University", said she does try not to seem scary after being intimidated by certain actors when her career started.

She was even wary she might alienate people when she was made a dame in 2003.

"People may look at me and think she is so scary... but it is not what you're trying to be," Mirren told a news conference on Friday ahead of the release of 3D "Monsters University".

The film is the prequel to Pixar and Disney's hit 2001 children's movie "Monsters, Inc." which made over $550 million at the international box office and is still one of the top 100 best earning movies.

The prequel goes back to when the small, green one-eyed monster Mike Wazowski (voiced by Billy Crystal) meets the huge, blue-and-purple monster Sulley (John Goodman) at Monsters University and the mismatched monsters can't stand each other.

Mirren voices Dean Hardscrabble, a dragon-like monster with a centipede body, who throws Wazowski and Sulley out of the School of Scaring, prompting them to join other monster misfits to compete in a Scare Games tournament and become best friends.

"Monsters University" is one of a list of family films being released this summer that includes 20th Century Fox's "Epic" in which singer Beyonce takes a voice part, "Despicable Me 2," "Turbo" with Ryan Reynolds as a racing snail, and "Smurfs 2".

Mirren, whose list of accolades from a career spanning nearly 50 years includes an Oscar for the 2006 film "The Queen", said voicing an animated character was a new challenge for her but she had learned that fear was something to conquer.

She said one of the best pieces of advice she was given came from a former headmistress who told her that the worst thing about fear is fear itself.

"I have lived by this ever since," said Mirren, stressing that she had had to work hard to get to where she is now.

"You have to get on with. My fears are my business and nobody else's and I deal with it. The other thing is to pretend that you are not frightened. Act."

"Monsters University" opens in US theatres on June 21 and in the UK from July 12.