With Sally May taking the family on a vacation, there's never a dull moment on the ranch with Hank the Cowdog around. In this adventure, Hank learns about a tool thief on the loose who uses a monkey to help him do his dirty work. And before long, Hank finds himself face-to-face with the pilfering primate! Can Hank help to stop the criminals in their tracks, or will the crooks make a monkey out of the Head of Ranch Security? Hank answers a challenge and creates the spectacular "The Impossible Chrysanthemum Song" and Slim performs his "Naptime on the Prarie" song for Hank and Drover.