The novel 'When Marnie Was There' by Joan G. Robinson was first published, providing the source material for the movie.
Studio Ponoc, which produced the film adaptation of 'When Marnie Was There,' was founded by former Studio Ghibli staff.
The animated movie 'When Marnie Was There,' produced by Studio Ponoc, was released in theaters in Japan.
The film was released internationally, reaching a global audience beyond Japan.