Gunga Ram (Nino Marcel), a young elephant trainer, swears vengeance on the killers of his sister Indria (Lisa Howard) and her husband on the orders of the religious fire-cult leaders, the High Priestess (June Foray) and Ashok (Victor Jory). The Maharajah of Bakore (Lou Krugman) disbelieves him and Gunga Ram is also opposed by the Maharajah's General Pollegar (Boris Karloff). Gunga Ram sets out to expose and destroy the fire shrine of Sabaka.

In India, Gunga Ram works as a mahout, or elephant driver, for the Maharajah of Bakore. When an older mahout named Koobah confesses to leaving the body of his dead elephant in the jungle and allowing her baby to escape, Gunga rescues the elephant baby and brings it to the delighted Maharajah. The Maharajah then fires Koobah, who threatens that the fire-demon Sabaka will avenge him. Outside the city, farmer Taru sends his wife to get Gunga because two followers of Sabaka, a dangerous fire-worshiping cult, are lurking outside their home. After the worshipers knock out Taru and burn down his house, the fire spreads throughout the area. With the help of his elephant Tilah, Gunga rescues Taru's baby from the crook of a tree, where the wife left him for safekeeping. The Maharajah later surveys the fire damage and gives Taru money to restore his home. The Maharajah then orders Gen. Pollegar to rout out Sabaka worshippers, but Pollegar is unable to find them. At Pollegar's insistence, the Maharajah orders Gunga to release his pet tiger Paku into the jungle, after which the boy visits his older sister Indira and her husband Kumar. Gunga is delighted to learn that Indira is pregnant. Soon after, Kumar is captured and strung up by the Sabaka leader Ashok because he and Taru have been trying to expose the cult. Ashok's assistant Luba then burns Kumar's home, and the fire kills Indira. Although the Sabaka High Priestess protests Ashok's violence, he insists that only fear will compel villagers to join with them. The Priestess then kills Ashok with a bite from a poisonous snake. After Kumar is burned to death on a flaming pyre, Gunga is grief-stricken by the loss of his family. The Maharajah, who is like a father to the boy, assigns Gunga to work on preparations for the festival of Dasara. Gunga, however, is intent on revenge, and learns that a villager named Domjik could identify his sister's killer. Gunga then incites Pollegar's ire by illegally entering military barracks to beg Pollegar to search the festival crowds for the murderer. Although the Maharajah is reluctant to punish Gunga because the boy's father died in the Maharajah's service, he orders him not to disrupt the festival. Nevertheless, while the Maharajah presides over the festival and entertains his British guest, Sir Cedric, Gunga gets Domjik to identify Sabaka worshiper Luba as Indira's killer. Gunga confronts Luba and the Priestess, who are disguised as entertainers, and imprisons them in the stables. The next day, however, the Maharajah releases them because Gunga has no proof of their crimes. He then punishes Gunga by demoting him to be a kitchen servant in the palace. After some time passes, the Maharajah allows Gunga to go to the jungle camp and give his elephant Tilah's new mahout some pointers. Gunga is still anxious to bring the Sabaka cultists to justice, and when he is reminded of Koobah because the new mahout has the same name, he sets out alone for Koobah's village. He is forced to kill a leopard in self-defense, and then discovers that Tilah has followed him. As they draw near the village, Gunga finds the Priestess and Luba in the midst of a ceremony. Luba captures Gunga, however, and the Priestess orders Koobah, who blames Gunga for his dismissal, to capture Tilah as well. Gunga is left tied-up in the vicinity of a ravenous tiger, but cuts through the ropes with a rock and discovers that the animal is his own loyal Paku. Gunga disrupts the Sabaka ritual when he appears with Paku, and informs the followers that the Priestess has deluded them. Luba is killed by Paku when he attacks Gunga, and the boy uses his survival as proof that the supposedly vengeful fire-demon does not exist. Gunga then takes the Priestess hostage and burns the statue of Sabaka. He returns to the city dressed in finery and, seated next to the Maharajah on his elephant, earns a bow from Pollegar.