Luck has run out for Tennyson Stillwater, former Lakers basketball star and owner of Tenn Hundred Acres Ranch in Lake Arrowhead, California.

First, a bad guy tries to steal his horse, then his ranch hand is brutally attacked and finally, Tennyson's stable is set on fire.

Fortunately for Tennyson, Casey along with Dylan, his American Cocker Spaniel pup, and their best friend Sumo-better known as Dylan's Dog Squad, are on the case. With Dylan's great nose, the bad guys don't stand a chance.