Bad Day at Riverbend is a 1995 children's book written by American writer Chris Van Allsburg.

On a quiet day at the Western town of Riverbend, local sheriff Ned Hardy sees a bright light across the hill.

When he heads out to investigate, he finds the local stagecoach driver covered in this mass and unable to speak.

Suddenly, a hand and crayon in van Allsburg's traditional art style appears.

It is then revealed that the strange matter was none other than crayon scribbles, and that Sheriff Hardy and Riverbend are part of a coloring book owned by a small boy.