"The rule would be this: whatever George saw, if it was runny or powdery or gooey, in it went . . ."

George Kranky's grandma is a grouch. She's always mean to George (and not much nicer to his parents either). One day, when George is put in charge of giving Grandma her medicine, he wonders if he can come up with his own remedy to try and help Grandma become less of a grump.

Using some rather unusual ingredients, George creates his magic medicine. But will it stop his grandma from being so horrible . . . or will it shoot sparks out of the top of her head?!

WARNING: Do NOT try to make George's Marvellous Medicine yourselves at home. It is likely to be extremely dangerous.