I was lucky enough to watch this film with subtitles before its original release in Japan, and I'm delighted that it's seeing an international release. In short, it's a story about five children who rescue a dog, only to find out that the dog's an alien (cue horrified looks from said children/fainting). The plot evolves from there as the dog takes them on a trip into space. In general the plot's amusing and fairly easy to follow; but it suffers from being overlong, which is the film's main problem, and children might have trouble following it and getting some of the references (one of the characters pretending to be a magical girl before she goes into a fight, for example). Otherwise, the animation is gorgeous, the character designs wonderful, and overall it's a film I'd rate highly and look forward to buying when it comes out. NB this is only talking about the subbed version, though; I can't comment on the quality or otherwise of the dubbed version.