Paul Giamatti has revealed that Twelve Years A Slave will be "grim".
The Rock Of Ages star is the latest addition to Steve McQueen's historical drama, alongside Michael Fassbender, Brad Pitt and Chiwetel Ejiofor.
"Shooting will start down in New Orleans this summer. It'll be interesting. It's a very grim film, a very big contrast to Rock Of Ages," said the actor.
Chiwetel stars as writer Solomon Northup, a married man from New York who was tricked and sold into slavery for 12 years in Steve's big-screen adaptation of Northup's 1853 autobiography
Paul has been cast as Freeman, the man who takes possession of the slaves when they first arrive in New Orleans.
"I play this real guy called Theophilus Freeman, who was the biggest slave trader in America at the time. His name was Freeman - how ironic!" Paul added.
"He did all kinds of things: he trained them to be able to play music and dance so I have a lot of horrifying scenes. It's pretty grotesque. Unfortunately, none of the white people come off very well - it's pretty grim."
The 45-year-old admitted he hasn't seen Steve's latest film: "I haven't seen Shame, but I saw Hunger and liked it very much. I'm interested to see Shame."
Martha Marcy May Marlene's Sarah Paulson and Raising Hope's Garret Dillahunt are also rumoured to have parts in the film, which is scheduled for a 2013 release.