When an email asking for volunteers to star opposite Scarlett Johansson appeared in Adam Pearson’s inbox, he replied saying he’d be willing ‘as a bit of a joke’, and thought no more about it.

But last weekend the film, Under The Skin, opened with the 26-year-old appearing opposite one of the most beautiful women in the world – and for much of the time, both are naked.

Adam, 26, first hit the screen as the memorable face of Channel 4’s groundbreaking series Beauty And The Beast: The Ugly Face Of Prejudice.

No joke: Adam Pearson stars alongside Scarlett Johansson in her new Hollywood blockbuster Under The Skin where they both shed their clothes

The show paired up those with facial disfigurements with image-obsessed WAGs, to explore society’s fixation  with physical perfection.

And he admits being quite used to shedding his clothes in public.

Adam, who has the genetic disorder neurofibromatosis, which causes  bump-like tumours beneath the skin and around the muscles and nerves, famously appeared in the poster campaign for the show, in just a pair of underpants à la David Beckham.

Yet even he was daunted by the prospect of ‘running around a field  with my tackle out’.

Against the odds: Mr Pearson, 26, suffers from the genetic disorder neurofibromatosis and first appeared on Beauty And The Beast: The Ugly Face Of Prejudice

Brave: Mr Pearson’s condition causes bump-like tumours beneath the skin and around the muscles and nerves, and he is an active campaigner for awareness and challenging society’s views on ‘facial equality’

His character is vital to the plot. Scarlett plays an alien who drives around Scotland in a van seducing men then doing horrible things to them. But meeting Adam is a turning point.

‘When people see a beautiful actress next to someone who is facially disfigured, they think he must be  the bad guy. But in this film, I’m the victim. It’s an interesting twist.

‘And my vulnerability shows her something about humanity that changes her.’

He adds: ‘In the end, the nude scene was a bigger deal for her than it was  for me. I’m totally comfortable in my own skin. The worst part was that I was bloody cold.’