Actors (L-R) Michael Gambon, Bonnie Wright, Daniel Radcliffe, Emma Watson, Rupert Grint and Tom Felton arrive for the premiere of "Harry Potter and the Half-Blood Prince" in New York, July 9, 2009. [Agencies]

LOS ANGELES- British boy wizard Harry Potter conjured his magic at box offices again, as the sixth film in the highly popular movie series earned a record $22.2 million at Wednesday midnight showings in the United States.

"Harry Potter and the Half-Blood Prince" from Warner Bros. beat the old record for Wednesday midnight screenings of $18.5 million held by 2008 Batman movie "The Dark Knight," said Hollywood.com Box Office President Paul Dergarabedian.

The debut "portends a huge and potentially record-breaking number for a single-day (box office) gross and best first five-day gross," among movies, Dergarabedian said.

The highest one-day U.S. box office record belongs to "The Dark Knight," which debuted on a Wednesday last summer to $67.1 million and went on to $203.7 million in its first five days. It earned $1 billion worldwide throughout its run in theaters.

The five previous "Potter" movies about the adventures of Harry and his friends at the Hogwarts school, based on the best-selling kids books by author J.K. Rowling, have raked in $4.5 billion worldwide since the first film in 2001.

But in recent weeks, some media reports have suggested the movies' fan base of teenagers and pre-teens may now be too old for the movies and that other franchises, such as the popular "Twilight" films, may steal some of Potter's audience magic.

Still, "Half-Blood Prince" hits theaters a full two years after the most recent "Harry Potter and the Order of the Phoenix," causing box office watchers to see a good deal of pent-up demand for the movie.

"Order of the Phoenix" also opened on a Wednesday and took in $140 million in its first five days, on the way to $938 million in total global ticket sales. Warner Bros. is a unit of Time Warner Inc.