The U.S. channel, Biography, will air a special documentary called The Harry Potter Kids which will profile actors Dan Radcliffe, Rupert Grint and Emma Watson later this month.
According to the site:
They were virtually unknown when they were cast in the first Harry Potter movie in 2000, but Daniel Radcliffe, Emma Watson, and Rupert Grint have since become worldwide stars. When Radcliffe won the coveted role as Harry in The Sorcerer's Stone, he was plucked from almost compete obscurity. Grint was a fan of the books and wanted a part in the films so much that he sent a video of himself rapping about how much he wanted the role. Watson was just 11 and had almost no acting experience when the film was released. Today, all the Potter kids are grown, especially Watson, who has been named one of the world's sexiest women by the magazine FHM.
The show will air on Wednesday, December 19th at 9 pm (ET) and be repeated on Thursday, December 20th at 1 am (ET). Stay tuned for video.