Sam comes home one day to find his family turning a little bit loopy - his mum is redecorating using hieroglyphics and his dad is building a pyramid in the back garden. He hopes it's just a weird new fashion, but then the strangeness starts to spread. With the help of his friends Ursula, Henry and Lucy the Goat, Sam must save his town from rampaging Roman rugby players, hairdressers turned cavewomen and a teacher who used to be a 'basket of kittens' but now wants to sacrifice the Year Ones to the Aztec sun god.