Emma Iverson is just settling into her new life at Little Tombstone when one cowboy from a neighboring ranch is murdered and another goes missing.
When Earp, Emma's ancient and irritable pug, drags in a single bloody work glove belonging to the missing man, she knows It's up to her to find the missing ranch hand before the murderer does.
Emma's investigation is complicated by a spate of mail thefts, attempts to turn Earp into a social media sensation, the acquisition of a potbellied piglet, and a local eccentric's insistence that his late mother is sending him cryptic messages through the crossword puzzles in the local paper.