Henley 's first acting job was playing Lucy Pevensie in the 2005 film The Lion , the Witch and the Wardrobe , based on the C.S. Lewis novel The Lion , the Witch and the Wardrobe . Henley made her debut as Lucy Pevensie in 2005 film The Lion , the Witch and the Wardrobe , based on the C.S. Lewis novel The Lion , the Witch and the Wardrobe .