An open casting call for the part of Luna Lovegood in the next Potter movie, Order of the Phoenix, had drawn the masses to Central Hall opposite Westminster Abbey.

Luna is a ditzy friend of Harry's and plays an important role in the fifth instalment of the massively successful series.

By 7.45am yesterday, the queue to try out had yet to officially open, but 1,000 girls and their parents were already in line, some since 10.30pm on Friday night.

"I heard about it on the radio, " said Shauna Crooke (13) from Arklow, Co Wicklow, who was with her mother Celine. "Everybody has the same chance, so you might as well take a shot at it, " Celine told the Sunday Tribune.

An hour later, and a thousand more had joined the queue, screaming every time a TV camera came around, taking photos of each other with their phones and frogmarching their parents to the only open cafe nearby, which was buckling under the pressure of hot chocolate orders.

"The atmosphere is class, " grinned Rachael Moore from Limerick city. Emilie O'Driscoll from Cork agreed, although her mother rolled her eyes, saying: "We're obviously totally mad." Such madness might stand to Emilie, who claimed a special affinity with Lovegood. "Luna is brilliant, crazy, out of this world completely . . . like me."

Shortly before 10am, the queue still hadn't moved, and was only growing in length.

Some mothers sat on deckchairs, glaring sleepily at Sudoku books, while their daughters gabbled with excitement.

Laura Jane Stacey (15), from Donaghadee, Co Down, mused on the motives of the Warner Brothers casting team as the doors finally opened just after 10am.

"They've got a look, they know who they're looking for.

They're just trying to find that person, I think."

The first Irish girl through the door was Sinead Creaner, who lingered outside with her dad when she was finished.

"We went into a room, filled out a form and said where we were from. They took our picture and said they'd get back to us. The whole thing lasted about five minutes."

So five, not even 15, minutes of fame, after three or four hours in line? "It was great fun, the excitement was brilliant, " Sinead insisted.

"Would you do it again?"

asked her father. "Yep!" she said, as more Irish girls awaited their turn. "I love Harry Potter, I've loved it since I was seven, " said Sinead Cullen (13) from Naas, Co Kildare, still far down the queue by midday.

"Harry Potter mania, " muttered a passerby.