Jessica Biel's boobs are real, and they're fantastic -- and Dame Helen Mirren has to check them out for herself!

At the Tuesday Nov. 20 premiere of Hitchcock, Biel, 30, and Mirren, 67, caught up on the red carpet -- where the Oscar-winning British actress marveled over Biel's stunning black Gucci gown, which revealed more than a little side-boob.

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As costar Toni Collette looked on, Mirren (herself resplendent in a black lace Dolce and Gabbana gown with gold details) moved in and actually placed her hand on Biel's right breast. To her credit, Biel (who wed Justin Timberlake back in October) didn't flinch.

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Based on director Alfred Hitchcock's 1961 making of his classic film Psycho, the film stars Anthony Hopkins in the title role, Mirren as his wife, Alma, plus Scarlett Johansson (as Janet Leigh), Biel (as Vera Miles) and Collette (as Peggy Robertson).

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Making the film was "amazing," Biel told reporters in NYC earlier this week. "This is the place where so much film history has happened and so many people have walked down those roads. It just felt ripe with history, kind of wonderful ghosts and spirits of time gone by . . . we were just transported to another time."

This article originally appeared on LOL! Helen Mirren Grabs Jessica Biel's Boob!