Mission Earth
The Voltarians want to conquer the planet Earth (Blito-P3, according to Voltarian astrocharts) to use as a gas station for their planned invasion of the galactic center. The Voltarians come to the conclusion that the indigenous inhabitants of Earth will destroy the planet through pollution and possibly war, which would disrupt the future of their invasion timetable. Royal Combat Engineer Jettero Heller, a character of perfection, incorruptibility, and astonishing ability, is assigned to save Earth from the Earthlings. Reaching New York City, he investigates the problem, unaware that he is being tracked and that factions on Voltar want his mission to fail.
Unknown to Heller, Earth is also the base of a secret operation conducted by the diabolically evil Lombar Hisst, head of the Voltarian Coordinated Information Apparatus (CIA), who seeks to usurp the Voltarian throne. To gain control, Hisst has been importing illegal narcotic drugs from Earth to enslave the heads of government on Voltar. Hisst works to make Heller fail in his mission.
Hisst assigns a stooge named Soltan Gris to supervise the mission to Earth, in order to sabotage it. Gris finds himself in possession of twelve tons of pure gold, which he tries to launder through a Swiss bank account and keep for himself. He then becomes a prisoner of two man-hating lesbians who end up marrying him, but not before various tortures are inflicted upon him. He has terrible money and girlfriend troubles, and he hires a hit man who eventually targets him.
Heller discovers a conspiracy headed by Delbert John Rockecenter, who keeps the population of Earth sedated with drugs and rock and roll music. Heller's attempts to break the demonic control of Earth by Rockecenter make him a target, and the corporation uses its most dangerous weapons to destroy him: psychiatry and psychology, and a mad, idealistic public relations genius by the name of J. Walter Madison, aka J. Warbler Madman. Madison initiates a wide-reaching public relations campaign to make Heller known to the world as the "Whiz Kid," but results in destroying Heller's reputation so that all of Heller's efforts to save the planet come to naught, as Madison's employer, Rockecenter, wanted. Heller's outstanding skills and abilities are reinforced by the arrival on Earth of his fiancée, the Countess Krak, and the alliance and friendship of the Mafia—specifically the Corleone family.
After a series of world-shattering events, which include the impact of an ice meteor on the Soviet Union, the world's entire oil supply being turned radioactive, and a black hole orbiting the Earth, Heller returns to Voltar to find that not only have Hisst's plans to enslave the government nearly succeeded, but Madison is starting a galactic civil war.
After the defeat of Hisst and Madison, a massive cover-up operation commences to wipe out the effects of PR, psychology, and psychiatry. All mention of these subjects is censored and the planet Earth is eradicated from all star charts and similar items. As far as the Voltarians are concerned, planet Earth no longer exists.
Volumes
The Invaders Plan (October 1985, ISBN 1-59212-022-9), 559 pages
Black Genesis (March 1986, ISBN 1-59212-023-7), 431 pages
The Enemy Within (May 1986, ISBN 1-59212-024-5), 393 pages
An Alien Affair (August 1986, ISBN 1-59212-025-3), 329 pages
Fortune of Fear (October 1986, ISBN 1-59212-026-1), 329 pages
Death Quest (January 1987, ISBN 1-59212-027-X), 490 pages
Voyage of Vengeance (May 1987, ISBN 1-59212-028-8), 381 pages
Disaster (June 1987, ISBN 1-59212-029-6), 337 pages
Villainy Victorious (September 1987, ISBN 1-59212-030-X), 410 pages
The Doomed Planet (September 1987, ISBN 1-59212-031-8), 333 pages
https://en.wikipedia.org/wiki/Mission_Earth_(novel_series)