Siblings Jimmy and Lotta join their aunt and uncle's traveling circus for an exciting summer. Jimmy becomes determined to sneak into the tiger cage and befriend the wild animals, ignoring all warnings of danger. Meanwhile, Fric, the jealous son of the tiger keeper, nearly tears apart Jimmy and Lotta's close friendship. Just when it seems harmony has been restored, Jimmy's beloved dog Lucky mysteriously disappears before a big performance. Jimmy and Lotta suspect foul play and set out to find Lucky, wondering if Fric is behind his disappearance. As mishaps continue plaguing the circus, the siblings realize someone is sabotaging the show. They race to uncover who is behind the crimes and rescue Lucky before the final curtain call. Their circus adventure becomes a quest filled with laughter, friendships, mysteries, and testing the boundaries of bravery.