The first clips from the fourth Harry Potter film will be shown on Saturday during the US network premiere of Harry Potter and the Chamber of Secrets.
Harry Potter and the Goblet of Fire is released on 18 November
Viewers will see excerpts and behind the scenes footage from Harry Potter and the Goblet of Fire, as well as interviews with its young stars.
The new film, directed by Mike Newell, is released in the UK on 18 November.
The sixth and penultimate Harry Potter book, Harry Potter and the Half-Blood Prince, will be published on 16 July.
In the fourth Potter film, JK Rowling's boy wizard is mysteriously selected to compete in the prestigious Triwizard Tournament against older students from Hogwarts and two rival schools from Europe.
Ralph Fiennes plays Harry's nemesis Lord Voldemort, while Miranda Richardson appears as gossip columnist Rita Skeeter.
The film will also see Harry get his first girlfriend in the form of Chinese pupil Cho Chang, played by newcomer Katie Leung.
"That's what I like about Harry - he's pathetic about the whole romance thing," said Radcliffe, 14.
"He doesn't know how to be around girls, which is great because he's a character for anyone who's ever been awkward with a girl. Which is probably every male anywhere in the world."
Emma Watson says things are also different for her character, apprentice witch Hermione Granger. "More than anything else she's on edge for much of the film," says the 15-year-old actress.
"She's more of a mother figure towards Harry and spends most of her time worrying about him."
Rupert Grint, who plays Harry's classmate Ron Weasley, says his character begins the film feeling frustrated about being overshadowed by his friend.
"Harry's always the hero, so he gets a bit annoyed," says the 16-year-old. "But in the end it's quite cool - he gets this wicked tournament that's really dangerous and exciting."