Thousands of screaming fans have turned out for the US premiere of Twilight.

The film follows teenager Isabella Swan who really does pick a bad boy when it comes to her first love - a vampire named Edward Cullen.

American director Catherine Hardwicke said: "Twilight is a very intense vampire romance.

"It's kind of like a young Romeo and Juliet where you have these two people that shouldn't be together.

"In this case they are different species, but they feel a strong connection that they can't be apart."

Young English actor Robert Pattinson, who played Cedric Diggory in Harry Potter and the Goblet of Fire, plays the vampire.

The movie's based on the book of the same name, the first book in a four-part series that has sold over 5.5 million copies in the US alone.

The film will be released in the UK on December 19.

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