Holy Hogwarts! 'Harry Potter and the Half-Blood Prince' finally hits theaters July 15, and the film's star trio -- Daniel Radcliffe, Emma Watson and Rupert Grint -- braved torrential rains on the U.K. red carpet for the film's world premiere!

"It's completely [like] the heavens opened -- it's pouring here!" said Emma beneath her umbrella. "Every year it's like torrential rain; it's like magic."

"The last premiere it was pretty rainy," agreed Rupert as he slogged through the soggy red carpet. "It must thunder as well. That sounds pretty horrible."

"This is Brit spirit -- we got through two wars like this!" joked Daniel. "For the next time here I'm certainly thinking these shoes might not be so usable after this, but I'm having fun. This is great."

In what could be the darkest, scariest and most exciting 'Potter' movie yet, the specter of the evil Voldemort (Ralph Fiennes) hangs over Harry (Radcliffe) and the students of Hogwarts as Dumbledore (Sir Michael Gambon) sets out to prepare our hero for the final battle (with a little help from new professor Horace Slughorn (Jim Broadbent), who may hold crucial information).

Meanwhile, hormones are racing among the students thanks to a powerful love potion and Harry, Ron (Grint) and Hermione (Watson) find themselves drawn to some, avoiding others and grappling with growing jealousy…

Directed by David Yates ('Harry Potter and the Order of the Phoenix'), the film also stars 'Potter' perennials Alan Rickman, Robbie Coltrane, Dame Maggie Smith, David Thewlis and Helena Bonham Carter.

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