Evanna Lynch has told an Irish newspaper she was shocked to find out she had won the role of Luna Lovegood in the next Potter film.
The young actress told the Drogheda Independent she had always wanted to play Luna and jumped at the chance of going to the open audition.
But even though she knew she'd make a good Luna, she was amazed to get the call saying she'd got the part.
"I thought it was some awful joke or they were testing me," said Evanna, 14.
Evanna, who is from Ireland, was chosen from 15,000 girls for the part.
She said when she found out about the open auditions in London she knew she had to go: "I knew if I didn't I probably would regret it for the rest of my life."
The Harry Potter fan said that although she felt a bit nervous, she didn't have to try too hard at the audition: "It wasn't like a Maths test where I have to strain to get it all right."
Evanna when she was younger
Evanna explained why she enjoys the Potter books: "Sometimes I'm stressed and I'm sick of things... in Harry Potter you're taken to this wonderful imaginary world where everything is so different."
Evanna also asked fans wait and see her in the film before deciding if she makes a good Luna.
She said: "To all the fans that are disappointed in the choice for Luna having seen the photo of me in the papers... that this was my first photo shoot and I felt a bit awkward.
"I promise to work hard to do a good Luna!"