The Crown star reveals all about playing Sherlock Holmes’s mysterious mother who spends 10 years in an asylum

This article first appeared in Radio Times magazine.

Why did this role appeal?

I loved the fact it wasn’t part of the Holmes canon, so we weren’t going to be disappointing avid devotees. It’s adventurous and irreverent and cheeky.

As Cordelia doesn’t appear in the books by Sir Arthur Conan Doyle, was there less pressure than if you’re playing a known character?

When I did [the film] Mrs Dalloway, there was certainly a pressure to realise what was in Virginia Woolf’s brilliant mind. It was nice not to be following lots of iterations of a story with this. I didn’t have any template for Cordelia and there was no competitive element in my mind. It’s an original piece of work.

Where do we first see Cordelia?

She’s in an asylum. It’s a gilded cage, and psychologically she’s definitely imprisoned, which must be terrible. You start to doubt your own reality, because if nobody is relating to what you’re experiencing, is it even true?

Do we see the real Cordelia after she leaves the asylum?

Yes, and that was joyous. She was locked up for 10 years; after that you would want to taste and experience everything that’s available to you. Any risk aversion goes out the window, because nothing can be worse than that.

Did you enjoy working with Hero [Fiennes Tiffin]?

Hero lives up to his name. He is truly heroic, charming and talented. Being from the acting stock that he’s from, he approaches it with endless questions and curiosity and humility. I’m going to get sentimental here, but there’s something very tender about working with young actors. The media would have you believe this generation is entitled and has no work ethic, but I would say the absolute opposite.

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