Tim Avery, an aspiring cartoonist, finds himself in a predicament when his dog stumbles upon the mask of Loki. Then after conceiving an infant son "born of the mask", he discovers just how looney child raising can be.

A loser finds success in the revenge-for-hire business.

It follows Monk, a brilliant detective with obsessive-compulsive disorder. He returns to solve one last case involving his stepdaughter Molly, a journalist preparing for her wedding.