The Academy of Motion Picture and Sciences continues its love affair with Dame Judi Dench, presenting her with her sixth Oscar nomination for her leading role in "Notes on a Scandal."

It's an affair that has blossomed quickly.

Dench, 72, has had a respectable, five-decade long career on the British stage and TV. Yet her film roles went mostly unnoticed by North American audiences until about 10 years ago, when she turned heads with her performance in "Mrs. Brown," directed by John Madden.

Since then, she has managed to defy the Hollywood notion that there are no decent roles for actresses over 40, scoring leading roles in such films as "Mrs. Henderson Presents" and "Iris" -- both of which earned her Oscar nods.

In "Notes on a Scandal," Dench plays a lonely and manipulative schoolteacher who develops an unhealthy obsession with a fellow teacher (played by Cate Blanchett), who is having an affair with a teenage student.

Dench has said the role was one of the hardest she has ever played and that she found it a relief to step out of the character at the end of every day of filming.

"I enjoyed it, but it was difficult to do," she told Canada AM from London. It was only the attentive direction of Richard Eyre that helped steer her through the dark story's rough waters, she says.

"I enjoyed it hugely working with Richard, who I know very, very well," she said.

"There could be many, many ways that we could have played so many of those scenes. But Richard has impeccable taste. And so yes, it was wonderful fun to do it - although it's a grim story."

Critics have said Dench's performance is matched perfectly by that of the mesmerizing Blanchett, who also earned a Best Supporting Actress nomination for her role.

Dench found it a pleasure to finally work with Blanchett.

"We were in 'The Shipping News' together but actually our paths never crossed. And so I was thrilled to work with her as well, absolutely thrilled."

Dench has become the kind of actress who somehow manages to lend a film gravitas by her mere presence, if even for the briefest of scenes in films such as "Shakespeare in Love" and the James Bond films.

But it was the former film that won Dench her only Oscar, for playing Elizabeth I, and it is the latter films that allow her the wittiest of lines.

In this year's "Casino Royale," Dench gets to poke fun at the anachronistic nature of the James Bond franchise itself, declaring, "[Expletive], I miss the Cold War."

"Yes, I wasn't allowed to say that for China," Dench remarked. "I had to re-dub it. It was: 'God, I miss the old times.' Not quite the same thing."

There is but one disappointing aspect of her Oscar nomination, she says: she will likely not be able to attend the Feb. 25 ceremony because she will be undergoing knee surgery.