The star of Harry Potter And The Cursed Child has said he had no idea who he was auditioning to play when he read for the hit production, but assumed it was a young Sirius Black.
Anthony Boyle, 22, had just left drama school when he won the role of Draco Malfoy's son Scorpius in the Harry Potter sequel.
The actor, who was named most promising newcomer at the Critics' Circle Theatre Awards, said he had only auditioned for the part of "lead boy" and did not know who his character was until he was given the script.
He said: "I was a massive fan and my father read the books to me and my brother when we were younger.
"The first time I read the script was in a locked room with a security guard there and another boy who was reading for Scorpius as well.
"At the time we were just reading for 'lead boy', and then we finally got to read the script and I'm very dyslexic and it took three hours to read two scripts.
"It was completely not what I was expecting.
"I was expecting it to be about Sirius Black for some reason, I don't know why, and I thought I was going to play a young Sirius Black (Harry's godfather).
"I was like 'who is this dude?'
"Scorpius Malfoy is a comedic character at the start, a bit of a clown, but the more I got emotionally involved in his story and the more I turned the page, the more I fell in love with him and had an emotional connection to him."
Boyle, from Belfast, said the fact he wears a blond wig in the show has helped preserve his anonymity, a luxury not enjoyed by Noma Dumezweni, who plays an adult Hermione Granger.
He said: "I'm like a secret agent.
"It's quite cool to walk about in Soho and not be recognised.
"Noma doesn't have a hope in hell of not being recognised."
However, that anonymity has not stopped people constantly asking him for tickets for the sold-out show.
Boyle added: "Every day I get 100 people asking for tickets, my dad will ring me and say people have stopped him in the street, people are pulling up in cars in the centre of Belfast going 'Give us tickets to the show!'"