For Orlando Bloom, this is the fifth film within the Lotr universe. The actor was first cast as the valiant elf-prince Legolas back in 2001's Fellowship, which became his breakthrough role. He has since gone on to star in other blockbusters like the Pirates of the Caribbean films and steal the hearts of millions of teenage fangirls, but his role in The Hobbit films is a return to his roots of sorts.

Orlando Bloom, The Hobbit: The Desolation Of Smaug Premiere
Orlando Bloom at the TLC Chinese Theatre.

Martin Freeman first played Frodo Baggins' uncle Bilbo back in Fellowship as well, however that was only a minor part, compared to his lead role in The Hobbit trilogy. In the mean time, he has acted in productions like BBC's The Office, 2003's romantic comedy Love Actually and of course, Freeman's cult role as John Watson in the BBC series Sherlock, to be revived in 2014.

Martin Freeman, The Hobbit La Premiere
Freeman at the film's LA Premiere.

Benedict Cumberbatch is part of a new crop of British actors to reach intenational stardom. He came into prominence internationally with his lead role in the BBC series Sherlock, a modern day adaptation of the Sherlock Holmes stories, headed by Stephen Moffat. Since Sherlock, Cumberbatch has gone on to play the villain Khan in Star Trek: Into Darkness, portray WikiLeaks founder Julian Assange in the 2013 flop The Fifth Estate and of course, voice Smaug the dragon in the second Hobbit film. 

Benedict Cumberbatch, Britannia Awards
Cumberbatch at the 2013 Britannia Awards.