Tucked away down a sleepy residential back alley in suburban Tokyo, Studio Ghibli, the headquarters of Hayao Miyazaki, is designed - by the visionary animator himself - in the shape of a boat. When I visited it five years ago, just before the release of his last film, Howl's Moving Castle, the team of young animators all had bowls of fish and terrapins on their desks. The result, Ponyo, is at last about to open in Britain: Miyazaki is a famously slow worker, and the delay has been compounded by a hold-up with distribution. But this irresistible marine fairy-tale is worth the wait.