She won an Oscar for her uncanny performance as Britain's Queen Elizabeth, but Helen Mirren's latest portrayal finds her as the power behind the throne - or, more precisely, the director's chair.

In Hitchcock, Mirren stars opposite Anthony Hopkins as legendary director Alfred Hitchcock's devoted wife Alma Reville, and early buzz has her as a contender for another Oscar nomination.

The film, which opens in limited release on Friday, explores the domestic life of one of Hollywood's most iconic and revered directors, set during the days of his struggle to put the ground-breaking 1960 classic Psycho on the silver screen.

Toggling back and forth between his on-set battles with censors and his cast including Janet Leigh (Scarlett Johansson), Vera Miles (Jessica Biel) and Tony Perkins (James D'Arcy), and his strained relationship with Alma as she copes with his well-documented obsession with his ravishing leading ladies, Hitchcock treats film fans to a glimpse of bygone Hollywood.

But it paints a more nuanced and sympathetic portrait of the director Hopkins called "a damaged man" than the recent television film The Girl, which dramatized the hell Hitchcock put Tippi Hedren through during filming of The Birds.

"It's a great role," Mirren said of Alma, a film editor and assistant director in her own right who ceded the spotlight to her husband, but as the film makes clear was involved in virtually every aspect of his films and even re-cut Psycho into the masterpiece it is known as today.

"So, you don't turn that down," she told Reuters.

Reuters