Helen Mirren has been a huge fan of the Fast & Furious franchise for some time now. It goes back, to at least, to 2015 when she told Yahoo Movies, “I so want to be a mad driver in a Fast and Furious movie. My claim to fame is I always do my own driving,” and it seems that this may have stuck in Diesel's mind upon hearing her interview and Mirren was cast for a "mysterious" role for the upcoming The Fate Of The Furious.
But, I am quite positive that she will play the Shaw brother's mother.
Let's take a look at the evidence:
1.) In late 2015 Diesel said this about Mirren to ET, “There are so many options! You’ve got Nathalie Emmanuel’s mother. You’ve got, of course, the matriarch to the Shaw brothers!”
2.) Variety scored an interview with Mirren in October and she dropped the largest hint, by "accident" I am sure. “I had always had a secret hankering to do Fast and Furious because I love driving cars. Of course, when I finally got my chance, I wasn’t driving the bloody car. I was in the back of an ambulance with Jason Statham (Deckard Shaw).”
3.) Finally, in an interview with Luke Evans (Owen Shaw) he had this to say when talking about his current medical situation, "People come around from comas, so who knows? He’s [Owen Shaw] in a military hospital because he’s the most wanted man in the world, but he’s got a very powerful brother, and he’s now got a mum as well, who’s played by Helen Mirren.”
This sells it for me. However, the picture above of Vin Diesel tells my that there is simply more to this story than meets the eye. For example, I am sure a movie script could find a way to make Vin the 3rd brother. What do you think?