WB pic casts spell over box office

Warner Bros.’ “Harry Potter and the Half-Blood Prince” grossed a magical $58.4 million from 4,275 theaters as it opened Wednesday at the domestic B.O., including a potent $22.2 million in midnight shows.

Film was pacing well ahead of the $44 million earned by “Harry Potter and the Order of the Phoenix” on its opening Wednesday exactly two years ago. “Order of the Phoenix” posted a five-day opening gross of $139.7 million.

“Half-Blood Prince’s” midnight runs were the best ever for any film, besting the $18 million earned by Warners’ “The Dark Knight” last summer, as well as the $16 million grossed by Paramount’s sequel “Transformers: Revenge of the Fallen” earlier this summer.

The strength of the midnight shows that those who grew up on Hogwarts’ most famous boy wizard may have gotten older — millions are now young adults — but remain loyal to the franchise.

Forecasts for the five-day opening vary. Some are predicting “Half-Blood Prince” would post a five-day domestic opening of $125 million to $150 million, while others put it higher.

“Transformers 2,” which grossed slightly more than $200 million in its five-day debut, posted an opening day gross of $62 million.

Pent-up demand could be playing a factor in the success of “Half-Blood Prince.” The last, and final, book, in J.K. Rowling’s series was published around the time that “Order of the Phoenix” was released, meaning two years have passed without a Harry Potter sighting.

An older fanbase could be part of the reason why the midnight shows were so strong.

Kids who were learning to read when the first book came out are in 1997 are older teens now, a ripe aud for midnight showings.

There’s always been an adult fanbase too, but parents with younger kids gravitate to daytime dates.

“Half-Blood Prince” has another ace up its magician’s sleeve when it comes to family fare: While the last two pics earned a PG-13 because of darker themes, “Half-Blood Prince” was awarded the more friendly PG rating, easing parents’ concern about whether to take younger tots. (Warners said it didn’t ask for the rating and assumed it would get a PG-13 classification.)

Film is opening day-and-date in every major overeas territory. “Harry Potter” films have been even more successful overseas, and no one’s willing to handicap how high “Half-Blood Price” will go in foreign realms. “Order of the Phoenix” grossed $646.2 million internationally and $292 million domestically.

Early estimates showed “Half-Blood Prince” grossing north of $3.2 million in Australia, the third best opening day gross ever after the last two “The Lord of the Rings” pics.

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