Lily James gets a "bright red rash" whenever she's nervous.

Lily James

Lily James

The 28-year-old actress might have had the starring role in 2015's 'Cinderella' after capturing the hearts of her fans as Lady Rose in the BBC period drama 'Downton Abbey', but the beauty admits she's still terrified of the auditioning process and has to wear "high-neck tops" to hide her fear-induced rash.

She told The Sun newspaper: "I always have to wear high-neck tops when I audition because I get this bright red rash. I just get so nervous. And I do it and I feel slightly dirty after, like, 'Oh I just had to give that' and then they're like 'OK, bye'. You walk out and you feel a little cheated."

And Lily's nerves could be down to her outlook on life, as the 'War and Peace' star - who is in a relationship with former 'Doctor Who' star Matt Smith - previously admitted to being "pessimistic".

Explaining how her pessimism impacts her professional life, she said: "I've noticed that when I'm acting I'll be like 'I want another take' but ... Probably because I'm in a vulnerable moment, I'll say 'I think I want to go again,' and then I'll try to explain myself.

"But when the camera [crew] wants to go again - because the focus or light was off - they'll say, 'One more,' and just do it. So I think that's what I'll try to do.

"We've all bought into this attitude of apologising and being modest, so that now when someone is actually direct and says what they want, you think they're rude. But they're not, they're just being clear!"

But Lily also admits she loves her job, and despite her nerves she doesn't see herself slowing down any time soon.

She said previously: "I'm definitely ambitious and I really love acting, so I want to keep working and getting better. I find it's like a drug: It's thrilling and addictive. Sometimes I think I'm tired, and I just want to go on holiday and not work.

"But then I read a script and I go, 'Oh f**k! I'd love to play that part!' I'd love to just be that and exist in that world - that is the best feeling."