Did some sly wizard slip Felix Felicis into our cornflakes? The magical potion known to make drinkers successful and lucky in all their endeavors is surely responsible for the just-announced news that Daniel Radcliffe has signed on to star in the final two "Harry Potter" films: "Harry Potter and the Half-Blood Prince" and "Harry Potter and the Deathly Hallows."

"Daniel signed several weeks ago and is very much looking forward to filming ['Half-Blood Prince'] in September," a spokesperson told MTV News on behalf of Radcliffe's publicist, Vanessa Davies.

Radcliffe's official return as the marked wizard ends weeks of speculation that he would be denied the role due to his performances in "Equus," a daringly adult play by Peter Shaffer known for its stark pessimism and implied violence. As Alan Strang, a young patient with a pathological fascination with horses, the 17-year-old actor was required to get fully nude onstage (see "Final 'Harry Potter' Book's Release Set As Films' Star Fights Controversy").

"Harry Potter and the Half-Blood Prince," the sixth book in author J.K. Rowling's blockbuster series, follows Harry as the wizarding world wages war around him. Primarily concerned with Harry's tutelage into the Dark Lord Voldemort's distant past, "Half-Blood Prince" is considered by many fans to be the darkest of the novels.

While not much beyond fan speculation can be said regarding "Harry Potter and the Deathly Hallows," the novel is sure to center on Harry's search for Voldemort's remaining Horcruxes, the treasured items that house part of the dark wizard's soul and keep him immortal (see "J.K. Rowling Reveals Further Details About Final 'Harry Potter' At Wednesday Event"). The book, which arrives on shelves July 21, is also likely to include the prophesied final battle between Harry and He-Who-Shall-Not-Be-Named.

To that end, fans will be watching "Harry Potter and the Order of the Phoenix," opening in theaters July 13, with a keen eye toward divining possible plot points for the series' conclusion.

Rupert Grint and Emma Watson, who play Harry's best friends, Ron Weasley and Hermione Granger, have not yet signed on for the remaining two films, although both have expressed interest in doing so.

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