Sarah Lancashire reveals huge difference playing 'sinister' role in new Netflix thriller with perfect RT score

Sarah Lancashire has been involved in some brilliant productions over the years, but perhaps her best known performance is as Catherine Cawood in BBC's Happy Valley.

The BAFTA-winning series tells the story of police sergeant Catherine, who is legal guardian to her grandson Ryan after her daughter Becky died by suicide.

Across three seasons, the show follows Catherine and her family as she confronts Ryan's father, Tommy Lee Royce (who she has always blamed for Becky's death), and navigates Ryan's interest in meeting him.

It's a totally different role from her new Netflix show Black Doves, which also stars Keira Knightley.

The drama - which already has a perfect 100 percent on Rotten Tomatoes - tells the story of spy Helen (played by Knightley) who has an affair with a man named Jason who's totally unaware of her 'secret identity'.

Meanwhile, Lancashire plays Reed, the boss of the Black Doves organisation who calls in Sam (played by Ben Whishaw) to protect Helen after Jason is killed.

Knightley stars in Black Doves (Netflix)

Speaking about the role, Lancashire told TalkRadio she 'adored' playing Reed.

She said: "[It] is really funny because people think she's really sinister. I mean, when I was playing her I just thought she was kind of firm but fair.

"She's enigmatic, and we don't know what she's thinking, and there's an ambiguity there.

"But I adored her because of the writing. Joe Barton's script is incredible.

"He's an extraordinary writer, and so you know, when you're looking at something clever and witty and tall, and that kind of writing doesn't come along every day, it's a joy to do."

Speaking about the role in comparison with her others, Lancashire told press: "Well, the joy is that I haven't played anybody like her before.

"She's a very self-contained character, but it's all going on inside. I think because she's given the best years of her life to an organisation which has probably robbed her of a partner, children, family, friends, it's grim."

Lancashire plays Reed in the Netflix show (Netflix)

People are already raving about the show online, with one fan writing on Twitter: "Impressed by Netflix casually dropping the ridiculously entertaining #BlackDoves at the end of the year without much fanfare as if it wasn't an absolute triumph. People are going to be quoting the dialogue for years."

While another said: "I’m on episode 5 of 6 and all I’ve been thinking about is rushing home to finish off Black Doves."

And a third added: "Just watched Black Doves on Netflix, a must watch. Exceptional work by @keiracknightley."

And a fourth commented: "BLACK DOVES is so engrossing. The kind of show that makes me wish I watched more TV."

You can catch Black Doves on Netflix now.