 The head had been sold to the antiques shop inadvertently, and is being sought by an antiquities dealer (Stanley Thornton) who knows it to be priceless.Two thieves (Doug and Des) who had earlier attempted to rob the antique shop, learn of a cash reward that Thornton is offering for Chico, and they attempt to capture him.The series centres on the children's adventures as they try to help Chico and to evade Thornton and the thieves.