The true story of a larger-than-life friendship. Twelve-year-old Tom (Parkinson) is the son of the zoo veterinarian at Belfast Zoo. As the bombs fall on Northern Ireland, during World War II, Tom's dad is drafted into the British army. With the animals' safety at stake, Tom must find a hiding place for the zoo's new addition: a baby elephant named Buster. Tom enlists his best friend, Pete (O'Reilly), and sensitive classmate Jane (Flain) to help him hide Buster.