Clarence the cross-eyed lion, normally a gentle soul, starts acting oddly after receiving a blow to the head in a jeep accident, becoming edgy, hard to control and growling at everybody. Dr. Tracy suspects that the blow has given Clarence amnesia, a diagnosis seemingly confirmed when Clarence suddenly takes a nasty swipe at Paula.
Nicky Sebastian, the son of an old neighbor, comes to Wameru to ask Tracy to sell him back a strip of land that had belonged to his father. Tracy tells him the land is needed as a buffer zone between the preserve and the neighboring cattle ranches. But Nicky actually intends to use the land as a hunting zone, and to start things in motion lets a truckload of cattle loose into the area, hoping to create just the situation Tracy most fears.
A big-game hunter, resentful of Tracy whom he blames for closing off land to his life's passion, forces the doctor to walk through wild territory on foot, hoping to prove that he will have to kill an animal to survive.
Due to her accidental switch of vials, Judy is injected with a virus which will kill her if she does not receive an antidote within 14 hours. Unfortunately, the chimp has also left the compound to look for a leopard cub she became attached to.
The Emir of Asambana's prize cheetah is sick, and may not be able to race in an important contest with a rival tribe. The Emir threatens to cut off the Wamera reserve from using the water on his property unless Dr. Tracy cures his cheetah in time for the race.
A pregnant black leopard, raised in a circus, is brought to Wameru, even though she has attacked her last trainer and killed her previous litters of cubs. Tracy hopes to change her behavior in the new environment.
Jack is out driving his jeep in the bush with Judy the chimp when the vehicle stalls out. With no water, they're forced to leave the jeep and try to make their way back through the drought-stricken jungle. Jack decides to follow a herd of giraffes, hoping that the animals will lead them to water.
A has-been stand-up comedian comes to Wameru to record animal sounds for his planned comeback act, doing animal impressions. But his attempts wind up creating more havoc than its worth for the compound.
While riding with Clarence and Judy, Mike's jeep overturns, pinning him underneath with a broken leg and a concussion. He must rely on Judy, who stays with him, and Clarence, whom the chimp gives the note to take back to Wameru for help.
Hedley accompanies an officer and his Nazi prisoner to look for microfilm which was buried near a watering hole in Wameru, and which is to be used as evidence against the prisoner and his cohorts. Unbeknownst to Hedley, however, is that the officer is not who he seems and is actually working with the prisoner. Though told to stay out of the watering hole area, Paula, thinking the reason is about nothing more than her secret birthday present, sends Judy there with a tape recorder.
Dr. Tracy, Paula and Mike try to clear animals out of a valley before hydraulic engineers blast a levee to divert the course of a river. The crew leader of the engineers gives them some time to do so, but one of his assistants, who is contemptuous of Wameru and resents taking orders from the younger crew leader, doesn't want to wait that long.
A jeep accident out in the bush results in Dr. Tracy being seriously injured. Paula and Judy the chimp are the only ones with him and have to find a way to get him safely back where he can get medical attention.
While testing whether a baby Indian elephant will be accepted by a herd of African elephants, Dr. Tracy and Mike are called away to help Hedley fight a fire, and have to leave the baby elephant with Judy. Before they can get back to them, the baby elephant is injured by a leopard and disappears.
Dr. Tracy and Jack ask Hedley to investigate the disappearance of several baby animals from the compound. Hedley soon finds the one responsible for the thefts: it's Judy the chimp, who's been bringing them as pets for the discarded elderly people of a nomadic tribe.
An attractive visitor to Wameru charms Mike and makes him a tempting offer of an important job in America with a foundation she is setting up. But Paula finds evidence that she may be misrepresenting the situation to him.
The nephew of a sultan who gave one of his tigers to Wameru as a gift visits and is welcomed by all. But only Judy the chimp realizes that the young man is actually there to kill the tiger, who mauled him during an initiation rite, and she continually frustrates his attempts to do so.
Judy the chimp and Clarence the lion "adopt" a vulture as their new friend and playmate, but they don't know that the bird is carrying a lethal virus. When Clarence becomes seriously ill, Judy runs off with the vulture, fearing that taking his blood for a serum will harm him.