This book honors the United States Coast Guard by telling the story of a little German Shepherd angel dog who works with a mermaid. Kai is washed into the sea and rescued by Amy, the mermaid daughter of King Neptune. Kai is plucked from Amy's arms by Angel Gabriel who deposits him on the deck of Captain Derek's Coast Guard cutter. Adopted by the crew, Kai helps to stop Buzz Blaster from plundering King Neptune's treasure.