The first childrens book written by the Godmother of British fantasy, Diana Wynne Jones.

OWN BACK LIMITEDREVENGE ARRANGED, PRICE ACCORDING TO TASK

Frank and Jess set up Own Back Limited because they need the money so why not offer to do the bad things people dont dare to do themselves? Their first customer is the neighbourhood bully. After his tooth is knocked out by Vernon Wilkins, he demands a tooth from Wilkins in revenge.

But the local witch, Biddy Iremonger, sees Own Back Limited as a threat to her own evil schemes. And when Biddy is angry, theres no end to the trouble shell cause . . .