The next-installment "Harry Potter" film will face a unique situation: It arrives more than a year after the completion of the literary saga. (The seventh and final book, "Harry Potter and Deathly Hallows," was published last summer.)

The big-screen versions, the filmmakers realize, now have to be separate entities.

"We had to make this film a worthy successor to the last — and a successful standalone film in its own right," says producer David Baron.

In "Harry Potter and the Half-Blood Prince," due in theaters Nov. 21, the focus is on the evolution of Harry's rival Draco Malfoy (Tom Felton) into a malevolent force. Also introduced: Potions teacher Professor Slughorn (Jim Broadbent).

Harry will whip up some particularly potent brews, thanks to his discovery of a book mysteriously marked "the property of the Half-Blood Prince."

Potter's alchemy has been consistently powerful at the box office. Last year's "Harry Potter and the Order of Phoenix" conjured up $292 million.

This time around, the danger may come from inside Hogwarts.

Harry, now 16, is suspicious of Malfoy, and he works with Dumbledore to retrieve memories pertaining to the evil Lord Voldemort.

But, being a teen as well as a wizard, he is drawn to Ginny Weasley (Bonnie Wright), younger sister of Ron (Rupert Grint).

Do Harry and Ginny share a magical snog?

"They're about to kiss," director David Yates says.

"Then the bloody Death Eaters turn up and cause all sorts of anarchy."