Sophie Skelton thinks having the 'Outlander' book series is a bit of a ''hindrance''.

The 23-year-old actress stars as Brianna Randall in the hit Amazon TV show and though it's based on Diana Gabaldon's novels, she would rather not refer back to the text because she thinks it can ''hold [her] back'' as her character is slightly different on paper than she is on screen.

She said: ''Having the books there to refer to is really advantageous, but at the same time it can hold you back because the characters are slightly different in the scripts - especially for Brianna.

''When we first see her in the book she and Claire Beauchamp Randall (played by Caitriona Balfe) have a lot of banter and it's quite light-hearted, whereas in the script that 20-year tension between the two of them is really laid on thick.

''Brianna actually comes across as a bit of a brat because she's very hard and very stoic and very guarded.

''Sometimes you find yourself wanting to pull towards the book version to keep loyal to the books and what the fans love, so although it's advantageous it's a bit of a hindrance because you almost feel you're fighting against that element when actually you just need to keep your head in the script.''

The story follows Claire Randall, a married World War II nurse who in 1945 finds herself transported back to Scotland in 1743, where she meets the Highland warrior Jamie Fraser (Sam Heughan) and becomes embroiled in the attempts to return James II of England and VII of Scotland to the throne of Great Britain.

Developed by Ronald D. Moore, the TV series is shot in the deep highlands of Scotland and Sophie said there was a ''weird calmness to it''.

She said: ''Some of the locations in the Highlands I'd actually been to before on family holidays and it was nice to revisit those.

''One that really comes to mind is where we have the stones. It's just a really beautiful location with this weird calmness to it.

''It was so silent and so still there was an eerie feel to it and that really helped with the scenes. You could just feel it in the atmosphere.''

'Outlander' series 3 continues Mondays exclusively on Amazon Prime Video.