Official website of Professor Layton and the Eternal Diva was updated with full length trailer, although I am not quite sure it can work as a proper preview to the film. And why no English subtitles?
The film is based on the popular Nintendo series of puzzle games about Professor Layton, investigating different mysteries. The film will continue the story of the last released game in the series, but I hope it will be also independent enough to appeal to viewers that are not familiar with the game.
At the beginning of the film Layton receives a letter from the famed opera singer, Jenice Kaitly inviting them to see the newest performance. She also asks Layton, Luke, and Remi for assistance in a mystery. She said one year ago, her seven year old friend, Melina, went missing, but returned later saying, 'She had gotten a hold of eternal life.' Naturally, the case fascinated Layton and his apprentices, so they head to the Crown Petone opera house. When they arrive something is very strange, the pianist, Ozro Vislar talks of a game, and the winner will win the 'eternal life'. It is up to Layton, Luke, and Remi to solve the mystery of the Eternal Diva before it is too late.
And another trailer, this time with English subtitles.
More stuff available on Official Website.