Actor Ewan McGregor is in negotiations to join the cast of Bryan Singer's Jack the Giant Killer for New Line Cinema.

The story centers on a young boy named Jack (Nicholas Hoult) who unwittingly breaks a long-standing peace between the humans and giants when he goes after a princess who the giants kidnapped. Ewan McGregor will portray the leader of the king's royal guard who helps in fighting off the giants. Stanley Tucci, Bill Nighy, and John Kassir are already on board as well.

Bryan Singer will direct from a script by Christopher McQuarrie, Mark Bomback, and Darren Lemke. The last major role to be cast is that of the princess, and, while no offers have been made, Australian actress Adelaide Kane and Eleanor Tomlinson (Alice in Wonderland) have emerged as the leading candidates.

Production is scheduled to start on Jack the Giant Killer next month in London.