Martha, a talking dog, tames her fears about the cargo hold in order to travel to Montana with her family, but she does not make herself very welcome at the dude ranch when she causes a cattle stampede.
Martha ends up at the local animal shelter after losing her collar, and when her family comes to claim her, Martha helps them organize a dog show to find families for her new canine friends.
Martha uses her canine detective skills to solve the mystery of the missing birthday cake and uncover the truth about a plot to rob the local jewelry store.
Martha the dog recounts her early days as a canine criminal after having been adopted by a thief and her partner before being captured by the police and brought to a shelter, where she ultimately met Helen.
