Tarzan, of Africa, is summoned to an unnamed Asian country to protect Kashi (Ricky Der), the youthful heir to the throne, from his evil uncle, Gishi Khan (Woody Strode).

Arriving by parachute from a light airplane and armed with a Spanish bolo hunting knife, Tarzan dons monk's robes and travels by boat to a monastery.

Tarzan and Khan battle each other in two of the challenge events of the fourth test which concludes with the third and final challenge event with each man fighting with swords on a wide mesh net suspended above large vats of boiling oil in which Khan dies by falling through the net into one of the boiling vats.

Some scenes were shot in the Temple of Buddha's Footprint, the first film ever granted permission to shoot at this holy site.

Forty-four years and four months old when the film was released, Jock Mahoney became the oldest actor to portray the apeman, a record that still stands.