"I love to garden," declares Helen Mirren. "I used to do a lot of vegetable gardening when I was sort of in my thirties and then life took me away from my vegetable garden. But I'm starting up again," she says, adding that she and her husband, director Taylor Hackford, have a home in Italy that has geothermal and solar heating. "It's completely off the grid."

Mirren, most recently seen as the horror director's wife in "Hitchcock," plays another real-life figure in "Phil Spector," in which she stars opposite Al Pacino in the role of Spector's lawyer, Linda Kenney Baden. Premiering March 24, the HBO movie, written, directed and produced by David Mamet, is inspired by the infamous murder trial in which Spector was convicted of killing actress Lana Clarkson, and is "an amalgam of fantasy and truth," says Mirren.

She stepped into the role on short notice when Bette Midler had to bow out due to an injury, and while that left little prep time and she was admittedly "terrified" of working with Pacino and speaking Mamet's dialogue, she jumped at the chance. "It was my dream come true," she says. She didn't meet the real Linda Baden until production had started, but did as much research as she could about the case and Spector. She didn't have to look far for personal insight: Hackford had worked with the music producer and "had some incredible stories about him. You get the sense of someone who permanently lived in a dream."

Mirren, currently starring in London's West End in the play "The Audience" as Queen Elizabeth II, will be back on the big screen in the action sequel "Red 2" in July. She'll also be heard in the animated comedy "Monsters University," opening June 21.

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