Catherine Walker: Her face is not as familiar as that of Ms Ronan or Mr Farrell – but theatre watchers speak her name with awe

“It was incredible, but there was a period of unemployment after that,” she says. There are many, many worse things. I didn’t know what I was going to do.”

By then was married. But I was just so focused on drama.”

She appears to have lived a fecund life during the English years. The virus was unshakable. She gets many opportunities to exploit that with her role as a widowed mother in Liam Gavin’s fascinating horror film A Dark Song. So it was a short courtship. She enjoyed the theatre. “Film and TV came later. You feel a bit of loss for the characters.”

Catherine has an expressive, flexible face, but it is the voice that really strikes you. Steve Oram plays an occultist who, while secluded in a remote mansion, talks her character through a necromancy ritual. And that was a weight. “I suppose I do see myself as a theatre actor,” she says with a hint of uneasiness. Her time at the RSC seems to have been deliciously exciting. I just jump off the mountain. “I wish I was one of those actors who can just switch it on, but I’m not,” she says. “Ah, I think I was. She won’t even let herself cry.”

Walker is clearly somebody who invests a lot of emotion in every performance. Walker laughs as she recalls crying when first arriving at the Swan Theatre in Stratford-upon-Avon. Maybe that was the start of theatre actors not being quite trusted with film and TV. One really feeds the other. When we got back from that, I felt that I had to get back to the sea. But theatre watchers speak Catherine’s name with awe. Yet she’ll be shooting until November

“Well, yes. “I was terrified. An early spell at the Royal Shakespeare Company offered invaluable grounding. Phew! I carried that with me. It’s grief that is solidified. “My way into the character was staying with the grief. With film or TV, when it’s on afterwards, you’re not connected to it. Two years ago she played Stella in A Streetcar Named Desire at the Gate. I coasted my way through school knowing that’s what I wanted to do and I regret that now. But we were all being packed away then. You are on your own. She has triumphed as Phaedra, Miss Julie, Hedda Gabler and Cordelia. Raised in Coolock, she had knocked up a few promising credits after graduating from the Gaiety School of Acting, but the move still felt like a significant risk. But it is Paris!” she sparkles. “I got a show in the Tricycle in London. That’s where all the actors rest these days. Some of my closest friends are still from that time.”

She subsequently divorced and now lives in a fashionable quarter of Dublin 8. But I do that sort of thing when I am terrified. Her face is not as familiar as that of Ms Ronan or Mr Farrell. My mother had a great love of theatre. I do occasionally think: I wish I had that degree.”

Did she become a dosser at school? One is vital for the other. “And we got married in the holidays from that. It comes as no great surprise to learn that she has been committed to the profession from an early age. She is about to head for Europe to shoot the third season of the lavish costume drama Versailles. If things had happened differently, she may have been lost to the homeland. There is a brittleness to it that responds usefully to the pressure of high emotion. It was a sea thing. You know what I mean?”

Walker overcame inevitable trials to construct one of the most intriguing CVs in contemporary Irish entertainment. A little less than 20 years ago, Catherine Walker did what so many of us then did and lunged for London. “I didn’t do any child acting,” she says. But I hate that separation. “But it was a sort of given that I was going to do that. “I met my husband at my second season at Stratford,” she says. So that was that,” she says. She has appeared in The Clinic and Holby City. For a few years, around the turn of the century, Catherine and her then husband lived an apparently cosy life in Brighton. She can’t let go of it. “Dublin is very important to me,” she says. Or does she? But it was on stage that she made her mark. She went to speech and drama classes. There is something about going on that theatre journey that is very different. Interestingly, so did a lot of the actors who were with me. “I had about a year. Such are the demands of the business that Walker finds herself forever reaching for the suitcase and the travel adapter. Then again, at that age, we feel we can accomplish anything.