Cumberbatch joins 'Slave' cast

Benedict Cumberbatch has joined the cast of 'Twelve Years a Slave'.

The 'Sherlock' star will star alongside Michael Fassbender and Brad Pitt in the movie which tells the real-life story of Solomon Northup, a black slave living in New York in the 1850s who is enticed to go on a trip to Washington only to end up being kidnapped and sold into slavery.