Granddad is a little absent minded and living in the hospital, but almost every day he receives a postcard depicting cherry blossoms. His grandson Tsuyoshi comes to visit him, and cannot help but notice these postcards from a mystery sender. One day, Tsuyoshi meets a taxi driver that knows the location of the cherry blossoms trees in the postcard. The grandson then sets out on a journey to find the location accompanied by a man called Jack.