Now that Zoe and Harvey are old enough to take part in the Grand Mountain treasure hunt to celebrate the founding of the park, they are determined to win the race with Lassie's help. While Zoe shows her headstrong nature by turning down her mother's help, doubt soon sets in when her big rival, Samantha, somehow manages to stay one step ahead of our heroes on each challenge. Luckily, Zoe and Harvey can count on the vision and foresight of their cunning canine teammate: Lassie!
