EXCLUSIVE: Ben Barnes, who played Prince Caspian in Fox’s fantasy franchise The Chronicles Of Narnia, is in negotiations for the starring role opposite Oscar winner Jeff Bridges in Warner Bros/Legendary PicturesSeventh Son, an adaptation of Joseph Delaney’s young-adult series. He replaces Sam Claflin, who was previous tipped for the role. Barnes will play Tom, the young apprentice to an exorcist (Bridges) who combats ghosts and witches in the 1700s. The pair must battle the queen of evil (Julianne Moore) as Tom falls for a young witch (Alicia Vikander). Sergei Bodrov is directing; Thunder Road’s Basil Iwanyk, Legendary’s Thomas Tull and Lionel Wigram are producing, and Jon Jashni and Alysia Cotter are exec producing. Barnes, repped by WME and Luber Roklin and CAM in the UK, also has booked Millennium’s Gently Down the Stream opposite Robert De Niro, Diane Keaton and Amanda Seyfried, and has a role in the indie film The Words with Bradley Cooper.