Russell Brand takes over the title role of the loveable but drunk billionaire in the remake of "Arthur," while Mirren plays his closest confidante and caretaker Hobson.
In the original film, Mirren's role was played by Sir John Gielgud. Mirren loves the fact that gender was not a factor in casting the remake, and she's happy to help break down those barriers.
"I think more of that, the better. There haven't been enough roles for women in the past 20, 30 years, and I think a lot of the roles that have been written for men could just as easily have been written for women," Mirren said.
Mirren believes the trend likely happens because women are changing in real life.
"And whenever that happens, you see that reflected in drama," Mirren said.
It's Mirren's hope that fans of the original film won't be put off by the fact that the comedy has been remade for a new generation.
"We're in a different day and age. We have different attitudes to addiction, and so things have shifted considerably," she said.
"Hopefully they'll come to our movie and enjoy it on a whole different level," Mirren said.
Russell plays homage all the time to Dudley Moore, who played the role of Arthur in the original.
"Russell is very different spirit from Dudley Moore. He has, I know, enormous respect for Dudley's performance," Mirren said. "Russell in himself is a very different kind of talent."
"Arthur" also stars Nick Nolte, Greta Gerwig and Luis Guzman. It's rated PG-13 and is in theaters on Friday.