It’s 1940, as war rages across Britain, eleven-year-old Eric finds comfort at London Zoo—especially with Gertrude the gorilla, his favourite animal. But when the bombs begin to fall, Eric knows he has to protect her. With the help of his zookeeper uncle, Eric and Gertrude escape the city. Hiding out by the sea, the unlikely trio stumble upon a daring Nazi plot—and suddenly, saving one gorilla turns into a mission to save the country.