The search for a collie stolen during a collie event challenges Jennet to solve a baffling mystery and ultimately to stay alive. A happy summer collie event in Woodsboro Park turns deadly when Ellalyn Zoller's beloved tricolor collie is snatched from her ex-pen and a bewildered 'changeling' collie is left in her place. Jennet volunteers to search for Rainbow, but she seems to have disappeared like the child, Celia Loring, who had vanished from the same park twenty years earlier. Can Jennet return Rainbow to her owner without falling into a trap set by the kidnapper?