The Defiant Agents is the third novel in The Time Traders series by Andre Norton. It was first published in 1962, and as of 2012, had been reprinted in ten editions with cover changes, as well as twice in a combined edition with Key Out of Time. It is part of Norton's Forerunner universe.

Operation Cochise: a carefully planned Western move to colonize a planet ahead of the Reds. Travis Fox had been an eager volunteer, but the morning he dragged himself half-conscious from the wrecked spaceship on the planet Topaz, he sensed the terror which would threaten the project.

Travis never learned why the ship had crashed, nor why he and the other Apache agents had been shot into space without warning and under Redax control, a machine which had returned them to ancestral mentality.

But the dangers on Topaz demanded free minds, for Travis soon realized that if the Reds already encamped beyond the mountains--a horde of barbaric Mongols completely dominated by their masters--discovered the secret of the eerie underground chamber in the towers hidden in a valley of mists, not only Topaz but Terra itself would be destroyed.

The Defiant Agents continues the series’ premise, an encounter between Western heroes, and the Russian Communists, and a mysterious alien race that has used time travel to alter Earth. Most interaction in this novel is in an American Indian-like setting.

Kirkus Reviews comments, “Andre Norton, a polished writer of science fiction, weaves [her] outlandish fare in patterns intricate enough to attract the most devoted addict. Do not try to contrive a consistent political allegory out of [her] flight into fantasy. This is pure science fiction....”

Andre Norton's ability to grip the reader and transport him to other worlds in space and time is well known. In this fast-paced adventure in which the struggle for domination of men's minds ranges from control of their prehistoric memories to the risk of unleashing a horror never meant for the hands of men, the author again proves to be "a superb storyteller whose skill draws the reader completely into a fantastic other-world," (Chicago Tribune).

This work is a sequel to both The Time Traders and Galactic Derelict. It is book 3 in the Time Traders series by Andre Norton, which also includes Key Out of Time.

Total Running Time (TRT): 6 hours, 32 min. Reading by Mark Nelson.

Andre Alice Norton (1912-2005) was an American writer of science fiction and fantasy with some works of historical fiction and contemporary fiction. She wrote primarily under the pen name Andre Norton, but also under Andrew North and Allen Weston. She was the first woman to be Gandalf Grand Master of Fantasy, first to be SFWA Grand Master, and first inducted by the Science Fiction and Fantasy Hall of Fame. In 2005, the Science Fiction and Fantasy Writers of America, announced the creation of the Andre Norton Award, to be given each year for an outstanding work of fantasy or science fiction for the young adult literature market.

The Defiant Agents - Äänikirja, Englanti, 2017