Stuart and his family (and Monty who stows away in the car) are going camping. When they get there, Stuart meets a smooth-talking skunk named Reeko, who is forced to give food to "The Beast" who is a cougar. Stuart and George join the "Lake Scouts," which Stuart has trouble in. But Reeko makes a deal with the Beast, resulting in Snowbell getting captured by her, and Stuart goes off on an adventure to save him. Eventually, Stuart and his friends attempt to trick the Beast into falling into a trap covered with sticks and leaves, which doesn't work. Reeko shows up with a group of forest animals. Reeko taunts the Beast, and the Beast roars at him. Reeko turns around, yells a battle cry, and sprays the Beast with all of his might. The Beast is taken away to a zoo, and Stuart earns a gold kerchief at last. Reeko tells Stuart that he (Reeko) was wrong to betray him. Stuart bids farewell to his friends as he, George, Eleanor, Frederick, Snowbell, and Monty head back home to New York.