Daniel Radcliffe has seen Eddie Redmayne in his Fantastic Beasts costume. And he’s not happy about it.

‘I got jeans and a zip top for ten years and you’ve got a great coat already?' said Radcliffe in a recent interview.

Sure, Daniel might not have the sartorial edge of Eddie Redmayne’s character, Newt Scamander, but we thought that as Harry he looked pretty swish in those dress robes at the Yule Ball in Goblet of Fire.

But a teenage wizard in the modern day can’t compete with a Magizoologist in the 1920s. Newt’s wearing that coat in 1926 – smack-bang in the middle of a decade it’s impossible to think of without the word ‘dapper’ springing to mind.

Daniel’s probably right to be a little jealous. I know I am; that coat is magnificent.

‘It’s interesting, my costume, because one of the main routes into this character is the way he moves,’ Eddie tells me. ‘With the tightness at the top of that coat, Newt’s a compact kind of guy, especially when you think about all the vials and magic he can fit in that coat. The trousers are slightly too short for him too, which works for the way I move as him.’

He smiles, caught for a second between Eddie and Newt. ‘And it’s the 1920s. I love the whole look of that era.’

Costume designer Colleen Atwood has recreated that era, one exquisite piece of clothing at a time. She scoured the world for vintage clothes and made costumes from scratch for each of the principal actors.

‘I made Eddie’s coat from some fabric I’d had around for years, from a play I did,’ Colleen says, on set between fittings. ‘I’d been hoarding it and I dyed it that colour for Newt.’

‘What colour is it, exactly? I want to guess emerald...’ I say.

‘Ah, no,’ she says. ‘I’d say it’s a dark peacock blue. Or technically, in fashion, we’d call it petrol. I knew from the script that Newt is true to the sky and the earth and land, and that’s what I depicted in the colours of his costume.

'The coat is a 1920s shape, in that it’s a bit ill-fitting but with a slightly modern silhouette. I have 12 duplicates,’ she says and, noticing my eyes widen, ‘Yes, I’ve got a dozen of Newt’s coats. He has to wear it a lot.’

That’s true, he really does. He runs in it, sneaks around in it, hides in it: that coat is the last thing that Eddie puts on before he steps into a scene as Newt, and the first thing he shrugs off gently when it’s over. It’s transformative; it makes him Newt.

But, if Colleen and Eddie don’t need all 12, maybe Dan could try one on?