At the city zoo in Rio lives a gorilla named Steve. Steve loves listening to music on the radio with his best friend, Antonio, the zookeeper. When Antonio leaves for the day, Steve feels the quiet of the night and lifts up the latch of his cage to escape and look for his friend. Luckily, he finds a big yellow hat at the tram stop to wear as the perfect disguise. But his adventure turns out to be bigger than he planned, because it's Carnival time in Rio! Fireworks and dancers, drums and tambourines, samba whistles and trombones -- can Steve find his friend amid one of the biggest festivals in the world?