Penny and Rio are two dogs who are complete opposites. Penny is curious and always on the go, while Rio prefers a good nap. At their new house, Penny discovers that their backyard is the meeting place for several different animals. Penny doesn't know why a cat, a groundhog, a squirrel, and an owl could possibly be meeting, but she knows she has to find out. She comes up with an ingenious plan for spying on them and discovers their plot. She has to stop them - but can she get her sister dog, Rio, to help her or will Rio decide that sleep is more important? Follow along as these two pet detectives, Penny and Rio solve the first of many cases in Penny and Rio: The Mysterious Backyard Meeting.