Elisabeth Moss was ''surprised'' by the success of 'The Handmaid's Tale'.

The 36-year-old actress - who plays Offred in the dystopian drama - admitted it was ''risky'' to adapt Margaret Atwood's beloved book into a TV series and she also thought viewers might think the series was too ''dark''.

She said: ''I was a little surprised when the show took off.

''It's dark and based on a book that's really important to people, so it was very risky.''

However, Elisabeth admitted she gets annoyed when people claim the show - which sees fertile women forced into sexual servitude - is too ''hard'' to watch because life is difficult.

She said:'' When people say the show is hard to watch, I get my hackles up.

''If you can't face our show, then how are you going to face what's actually happening in the world?

''It's shockingly relevant. It's important to hold that mirror up to society and to ourselves to try to get people to face what's going on, before it's too late.''

Despite her dark role, Elisabeth insisted she finds it easy to get out of character after filming.

She told Radio Times magazine: ''I'm very good at shaking it off. As soon as we've finished a scene, I'm done. I'm like, 'Where's my coffee?'

''I'm not somebody who stays in the moment. If I stayed in character, I would lose track of reality.''

And the former 'Mad Men' actress relishes the challenge of shooting a tough scene.

She said: ''The tougher scenes are my favourite to work on.

''I'm an actor, so I don't want to sit around looking happy all the time. If I do that, I get bored.

''I'm not a dark person, but my favourite days involve the emotional material.''