When Kalle, a normal 10-year-old boy gets a sister--a weird sister with two skin flaps on her back that look like wings--life becomes a struggle. No one but Kalle sees the true nature of his sister's odd appendages and soon she is off to the renowned Plastic Palace clinic of cosmetic surgery to have them removed. Determined to prevent the amputation of his sister's wings, Kalle sets out on a rescue mission. On the road, he meets Alf, a butter-fingered mechanic, who agrees to help him. Together, they roar off in Alf's white 1960 Cadillac in a race against time through an autumn-coloured world of song and dance.