A stay in the city of San Diego seems like it might be just the break the girls need--lovely weather and great sights to see. That is until they hear some animals handlers at Captain Swashbuckler's Adventure Park talking about the trouble they've been having keeping all the animals in their habitats. Mia and her sisters cannot resist a challenge, and they talk Miss Julia and their parents into another visit to the educational amusement park to search for clues as to what or who is helping the animals escape. Can Mia save the day and help keep the beloved animals safe?