Zoologist Gregg O’Hara (Bill Paxton) is exploring the remote Pangani Mountains in Central Africa when he comes upon an incredible discovery – an astonishing 15-foot gorilla. Fearsome and dangerous when provoked, he is tame in the hands of Jill (Charlize Theron), the 21-year-old orphan who raised the gorilla and named him Joe. When poachers threaten Joe’s life, Gregg and Jill rescue Joe by moving him to a California animal preserve.

Joe is not safe for long, as his notoriety makes him a target for a ruthless poacher. Threatened and confused, Joe escapes from captivity. Jill and Gregg race to save Joe’s life before he is destroyed by the authorities, and the chase culminates in an incredible and selfless display of courage by the mighty Joe, proving that within his fearsome frame beats a noble and heroic heart.