A mouse is punished in an unusual way for stealing bacon from an old woman with magical powers. Pleasant watercolor illustrations depict his plight. The spell cast over Jonathan will cause him to change to the color of whatever he eats. Toby, a dog, is the first witness when he comes upon an orange mouse munching a carrot. Jonathan is horror-stricken at the news and feverishly eats other foods provided for him by the dog. Cabbage turns him green, cheese yellow, a tomato red. Desolate, he eats some forget-me-nots. Even the cat scorns a blue mouse. Then the dog gets a pair of gray trousers. Once again, Jonathan is gray, but how unpalatable trousers are! A simple tale, nicely told.