Mercy the pig's love of buttered toast leads to the capture of a small thief who would rather be a cowboy. Leroy Ninker is a small man with a big dream: he wants to be a cowboy, but for now he's just a thief. Nosy neighbors, astonished firemen, a puzzled policeman, and the ever-doting Watsons return for a new tongue-in-snout adventure about Kate DiCamillo's delightfully single-minded pig.

After Mercy Watson follows the delightful scent and delicious taste of the pansies her thoughtful neighbors plant to beautify their yard, animal control officer Francine Poulet is called out to handle the case, which brings unexpected results.

Stella Endicott wants to go caroling on a snowy winter night, but no one wants to join her, except for the pig, the cat, and the horse she picks up on the way.