John Watson is nervous being the only dog at his new school, Baker Elementary. But when he takes an interest in fellow student, Sherlock Holmes, the two become unlikely, and sometimes contentious, friends. Together they deal with bullies, track down lost toys, investigate stolen playground equipment, and even face an unseen threat terrorizing the school halls. All the while Watson tries to help Sherlock make friends with his fellow students and Sherlock tries to help Watson become a better detective.