Discovery of the film that was a “phantom” when the movie “Grave of the Fireflies” was first released

It has been revealed that the ``phantom'' film from when animation director Isao Takahata's movie ``Grave of the Fireflies'' was originally released was left behind. Some scenes are drawn using only lines, and an expert says, ``This is a valuable discovery, as it has similarities to later works that focused on expression using lines.''