Willem Dafoe has joined the cast of 'Nymphomaniac'.

The veteran actor will work with controversial Danish director Lars Von Trier for a third time on the movie, after previously having roles in 'Manderlay' and 'Antichrist'.

Also confirmed in the full cast is another Trier regular, Udo Kier, who has appeared in seven of the director's previous works.

The racy film - which follows a sex addict Joe, played by Charlotte Gainsbourg, recounting her life and sexual experiences - has also attracted a number of Hollywood stars to sign up, including Shia LaBeouf, Uma Thurman, Jamie Bell, Christian Slater and Stellan Skarsgard.

Shia recently admitted the cast have signed up for engaging in real sex scenes on camera, which he is willing to do for the sake of his art.

He said: ''There's a disclaimer at the top of the script that basically says we're doing it for real. Everything that is illegal, we'll shoot in blurred images. Other than that, everything is happening.''

Speaking of Trier, he added: ''He's very dangerous. He's the most dangerous dude I've ever showed up for. I'm terrified.''

The film will be available in two versions - hardcore and softcore - when it is released in 2013.