Actress Anna Maxwell Martin has revealed that she has a secret weapon when it comes to acting certain roles – her naturally sad-looking face.

The 36-year-old, currently starring in BBC One drama Death Comes To Pemberley, sees her playing Jane Austen stalwart Elizabeth Darcy alongside Matthew Rhys as Mr Darcy.

And there’s plenty of opportunity for her to show off those concerned facial expressions after villainous Mr Wickham is accused of committing murder on the grounds of her home.

“I’m only good at dark and intense,” Anna admitted to the Radio Times.

I’m not very good at laughing or smiling in acting… I don’t know, I just have a naturally sad face. I’m quite a happy person in real life.”

The actress added that her looks had actually helped her career – since she is not thought of as a sex symbol.

 “I’m really lucky in that I think it’s much harder as an actress if you’re typically beautiful and you’re forging your way down that road,” she explained.

“It’s very easy to be offered parts that are overly sexualised, overly scrutinised, slightly dumbed down. I’m lucky enough to be offered character parts or misery guts – something with a bit of juice in them.”