Callum Turner joins J.K. Rowling’s Wizarding World as the older brother of Newt Scamander in Fantastic Beasts: The Crimes of Grindelwald. And while he and Eddie Redmayne have a lot in common, their onscreen characters couldn’t be more different.

There are differing views on how Callum Turner landed the role of Theseus Scamander – brother to Eddie Redmayne’s magiozoologist Newt – in Fantastic Beasts: The Crimes of Grindelwald.

“I thought it was because I looked like Eddie Redmayne, but actually it’s not. It’s ‘cause I broke my wand [during the screen test],” laughs Turner, who grew up reading the Harry Potter books and admits he went to bed most nights hoping Hedwig or one of her owl friends would drop a letter saying he was going to Hogwarts.

According to Redmayne, however, it was an impromptu brotherly kiss on the forehead during the audition that sealed the deal.

“What almost didn’t get him the part was the fact that he did this brilliant thing called War and Peace, a book you may have heard of,” he adds. “BBC did an adaptation of it recently, which Callum was in. I was watching it with my wife Hannah, and when he came on screen, Hannah went, ‘Oh my God, that guy looks like you, but he’s just taller and darker and maybe more handsome.’

“So when Callum was auditioning for this, [director] David Yates said, ‘I’ve got this lovely actor who’s coming in to audition with you.’  And Callum literally walked through the door, and I was like, ‘Of course. It’s him,’” laughs Redmayne.

Introduced in The Crimes of Grindelwald, Newt’s older brother Theseus is a war hero who now holds a lofty position at the Ministry of Magic, heading the Auror Office. He’s the complete opposite of the shy Newt, which is how Turner approached the role.

“Even though they’re very similar – and the similarities are through their stubbornness, and being successful, driven and powerful – it wouldn’t make sense if they were the same.

“There were little things, like having ankle swingers, I call them, in the costume; that was a nod to being brothers. But then, the writing’s so brilliant and layered and textured that it was awfully free, really.”

For Redmayne, who has two brothers in real life, creating a fraternal dynamic with Turner on screen was easy.

“Weirdly, my older brother James is a bit like Theseus,” he explains. “He’s sort of this incredibly talented schoolboy/hero, formidable at sport, and just a wonderful, very successful human being. And there was a moment when James came to the set where I just sort of looked around the corner and found Callum and him having this sort of quite deep and meaningful conversation. I felt like saying something like, ‘Whoa-whoa-whoa, wait a second, step away from the vehicle.’ But the amazing thing about Callum and I, weirdly, is we grew up about a hundred metres from each other. It’s sort of surreal that we come from the same part of London.”

Producer David Heyman credits Turner with bringing authority and authenticity to the part. “I mean, you really believe that he’s Eddie’s brother… they are opposites and yet are very clearly brothers. And what he did so brilliantly in his audition – and it’s in Jo’s [J.K. Rowling’s] writing, as well – was bring a sense that these two people have a history.  So, there is affection but also a little bit of that brotherly or fraternal thing, which I think really comes across. And, you know, Theseus is a Ministry man. Newt is not a Ministry man.

That brotherly love, I think, is one of the heartbeats of the film.

Theseus is also engaged to a former crush of Newt’s, Leta Lestrange (Zoë Kravitz), which leads to some awkward moments between the brothers when they join forces against the threat of dark wizard Grindelwald (Johnny Depp).

Moreover, it’s their respective relationships with Leta that adds to the sense of sibling rivalry.

“Leta and Newt are very similar,” says Turner. “They’re outcasts and slightly different; they’re not accepted, whereas Theseus is – and that’s what drives him, in a sense. That’s what he can provide for Leta, and vice versa. You know, opposites attract in relationships. People have different qualities. She provides the things that are exciting and otherworldly that he then latches onto.

“And with Newt, the thing that drives Theseus actually is love. It’s very important to him, the brotherly thing.  It’s not that he’s the older brother and, ‘You’re going to do what I say.’  There is that element to it, too, but I think the friction really is in Theseus suffocating Newt. Theseus is overprotective of Newt and doesn’t allow him space. But really that comes out of love.”

Heyman notes that J.K. Rowling’s characters are never simply black and white.

“You look at Snape, you look at Dumbledore – you may view Snape as a baddie for a long time, but actually you really come to realise why he is as he is. And he has such incredible qualities. Dumbledore has his demons, which we will explore further. Newt has issues; he’s a wonderful leading character, but he doesn’t really want to engage. It’s about creating rich and complex characters who have their demons.

“And thinking about Theseus, you say he’s a good guy, but he’s such a Ministry man that he’s bought into that view. He’s a follower in a way. He’s followed the Ministry way to a T.”

While Theseus’s decision to fight the good fight has often put him at odds with his brother, in The Crimes of Grindelwald there is much more at stake.

“The wizarding world is splitting into camps, and Theseus warns Newt that everyone, even he, is going to have to decide which one they’re in,” says Turner ominously.

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