When PB3’s robot, Robin, stops working, thedoctor on Planet P3 tells PB3 to throw her in therubbish and buy a new robot. There is a needle made of wood that is broken and cannot bereplaced because there are now no trees on Planet3. PB3 goes off to Earth to look for a needle made of wood to save his friend. During his search hefinds out about recycling and also about children who collect things to sell on rubbish tips. Will the children be able to help PB3 and will PB3 and Robin be able to help the children?