Holliday Grainger said she would have loved to have played a Harry Potter villain, as she prepares to star in a TV adaptation of another of JK Rowling’s works.

The actress, who stars alongside Tom Burke in BBC One drama Strike based on Rowling’s Cormoran Strike crime novels, also told of the “pressure” of portraying one of the author’s beloved characters.

Grainger said that if the chance to appear in the Potter films had been an option for her, she had a type of role in mind.

Holliday GraingerHolliday Grainger (Dominic Lipinski/PA)

She told the Press Association: “I always really liked Ginny (Weasley) in the books but, having said that, if I was going to go back and be cast in a Harry Potter film I would definitely have to be a baddie.

“It’s far more fun. To be a JK Rowling baddie in the Harry Potter world would be amazing.”

Grainger plays Robin Ellacott, the very non-villainous assistant to Burke’s gruff, emotionally and physically damaged private detective Cormoran in the TV series, adapted from Rowling’s novels The Cuckoo’s Calling, The Silkworm and Career of Evil, all written under the pseudonym Robert Galbraith.

Grainger said: “I met (Rowling) initially at the read-throughs and we just talked generally about the series.

“All of her notes were very positive. Because her notes are so vivid it felt when we started like everyone was already on the same page and that there weren’t too many big character questions. It’s all so evident in the writing.”

Tom BurkeTom Burke in Strike – The Cuckoo’s Calling (BBC/Bronte Films/Steffan Hill)

Grainger said that she does feel some pressure over her portrayal of a Rowling character, particularly because Robin resonates with readers.

She said: “I hadn’t been (worried) because I felt such a personal connection with Robin.”

But she said she soon learned that many women “engaged” with Robin and really loved the character.

Grainger, who has appeared in films including Great Expectations and Anna Karenina, said: “So then there was pressure to come across as likeable as she comes across in the book.”

War and Peace and The Musketeers star Burke said that being complimented by Rowling over his portrayal of her detective was “the biggest relief in the world”.

He said one of the biggest challenges with Strike was portraying an amputee, because Cormoran was injured from his time fighting in Afghanistan.

Asked about the most challenging part of the role, he said: “Achieving the authenticity – I think authenticity is a dodgy word because one is always moving towards authenticity as it’s not real and fiction – but making sure one honoured the detail of everything with the leg…

“That was where one felt one had one’s work cut out.”

The Strike series begins with the adaptation of global bestseller The Cuckoo’s Calling, which sees Cormoran and Robin uncover the mysterious death of famous model Lula Landry.

Strike – The Cuckoo’s Calling begins on August 27 at 9pm on BBC One.