Salaryman, Usagi Oishi, finds his house too small for his growing children. Moguro offers him a vacant house in the countryside, but they are warned not to enter a foggy valley. His family like it, so they move there and he visits on weekends. However when he stays in the city on weekend, his family are lured into the valley. When he arrives home his family are gone, but he joins them on a farm in the valley which exists in the past where life was much more simple.