Summer has returned. Eating watermelon, Natsuko and her grown son Kenji laugh about the hellish heat they endured when their air conditioner broke the previous year. When they finally reach for the remote for the first time this summer, the unit does not respond no matter how many times they press the button. “Mom, the air conditioner broke again this year.” And so another sweaty summer vacation begins for Natsuko and Kenji.