Professor Layton and the Sword of Spirits

Hershel Layton, Luke Triton and Emmy Altava recieve a letter stating that Jean Descole has found the lost Temple of Demostrane witch houses the mystical Sword of Spirits. The sword can take a humans soul and give it to the wielder as well as letting the wielder use the victims voice to trick other people. But the strangest thing about it is that is was sent by a man who calls himself Norval C. Layton, Professor Laytons brother...