On more than one occasion in new British horror fantasy series The Fades, Scottish actor Iain De Caestecker was required to have moths pouring out of his mouth.
But forget computer wizardry - this was the real thing.
"We had a special mouthguard - it was like a rubber see-through mouthguard which I put in my mouth and they just shoved moths in there," De Caestecker says. "It's quite horrible. I used to just spit them out. Sometimes they wouldn't want to come out either and they'd just sit in your mouth."
The Fades, created by Skins and This Is England 86 writer Jack Thorne, is not for the squeamish.
But it is a cracking addition to what has become a defining genre of British television in recent years - the smart supernatural drama -from Torchwood to Misfits to Being Human.
The Fades revolves around shy teenager Paul (De Caestecker) who has just found out that he is an 'angelic' - one of a select group of humans who can see the spirits of the dead, known as "fades".
Many fades are trapped on Earth after something went awry with their ability to ascend to the next plane and they're not happy about it.
"They can see everyone, but no-one else can see them," De Caestecker says.
"The fades have no sense of touch or smell - they're basically just rotting on Earth for all eternity.
"The angelics are kind of protectors of the divide between humans and fades and as the story starts there's one particular fade who has found a way to start fighting back - he's killing humans. So there's a war coming and Paul finds out he's got powers, which he can't explain, and he has to kind of figure out what they're for."
Unfortunately, at the same time he's lumped with the responsibility of saving the world from the zombie-like fades, Paul is hitting his stride as a teenager and even attracting the attention of a cute member of the opposite sex.
"He's conflicted. He's having these really vivid nightmares, which he doesn't know if they're true or not, and he's got all these sort of normal troubles which are associated with a 17-year-old."
But with the body count rising at an alarming rate, it's soon clear the fades are transforming into a different kind of monster with the potential to wipe out Paul's small town and beyond.
"I think (creator) Jack was quite keen to say that the fades were a new breed of supernatural creature, you've got vampires and werewolves, but he wanted the fades to be something new, so that's quite a cool notion."
The Fades features a strong ensemble cast including Johnny Harris (Snow White and the Huntsman), Natalie Dormer (The Tudors' Anne Boleyn), Daniel Kaluuya (Johnny English Reborn) and Tom Ellis (Miranda).
It was even named best drama at this year's Bafta awards.
But you know things are tough at the BBC when a show with good reviews, strong ratings and the country's top television honour still gets cancelled after one season.
Thorne said massive cutbacks meant the show's parent channel, BBC Three, only had enough money to keep one series and they picked up Being Human for a fifth season instead of renewing The Fades.
"It's a bit sad," De Caestecker says. "In the same respect it's quite nice knowing we've got a standalone series now and it will always be there and nothing can be tainted."
He hasn't been tempted to storm the BBC offices brandishing the Bafta to demand a second series, then?
"No," he laughs. "I'd get in too much trouble if I did something like that."
What: The Fades
When: Tuesday, 9.20pm
- © Fairfax NZ News
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