Somewhere, from among the four human-settled worlds of the Warden Diamond, hostile aliens were spying on Earth. But no agent could be sent to investigate and report back. All trips to the Warden worlds were one-way. There, a microscopic symbiont invaded all life forms, after which life became impossible outside the Warden system. The same organism destroyed any form of machinery, so no message could be beamed back by normal means. That called for extraordinary means, of course. One agent was chosen, then four men were stripped of their own minds and personalities, and his was imposed upon them. Hooked up properly, he could then receive their reports, without ever leaving safe territory. Each man was assigned one world to conquer. His mission was first to find the Overlord of that world and kill him, then to take over his link with the aliens. Of course all this must be done with no help beyond his own naked ability... This first book of Jack Chalker's epic tetralogy deals with Cal Tremon, who was sent to Lilith, a planet that was a paradise - but a paradise designed in hell! -from the back cover

Grand Scam Robots were infiltrating the Federation. Someone was kidnapping people and substituting indetectable, synthetic imitations. Somewhere, aliens were studying the Federation, using techniques beyond human developments. The trail led back to Cerberus and the Lord who ruled that planet. Cerberus, however, was one of the Warden Worlds - and those Worlds were the untouchables of space. There a strange microscopic life-form invaded all matter, and anyone so infected died on leaving those Worlds. Men could go there, but never return. But the Federation had its own techniques. They took a criminal named Qwin Zhang and stripped her mind of all memory and personality. Then they poured into that empty receptacle the full mind of the Federation's best operative. They exiled her to the prison world of Cerberus. The mission: Find the Lord who ruled, kill him, and take over. Too bad there were things about Cerberus they couldn't know!

They took the body of Park Lacoch and stripped away his mind. Then they stuck him aboard a spaceship and exiled him to Charon, from which no return was possible. And just when he thought things couldn't get any worse, Park found himself transformed into a changeling—a half-beast, half-man, with the beast rapidly gaining ascendancy . . .

The Confederacy's grand scheme seemed to be working. They had substituted the mind of their best operator for the minds of four criminals - every one a top assassin - and sent one to each of the four Warden worlds to eliminate the resident Lord there. The agents on Lilith, Cerberus, and Charon had already reported in - success! Now only Taran Bul's mission on Medusa remained. On this frozen ice world, Bul quickly joined an on-going conspiracy determined to overthrow the hated dictator Lord Talant Ypsir - the rebel's mission suited his perfectly. But a combination of alien menace and Ypsir's secret power proved too much for Bul. At last, the operator over all - the Agent With No Name - had to prove his ability...with everything stacked against him! In this volume of his most gripping series, Jack Chalker brings to a grand conclusion the epic confrontation between the mighty confederacy and the small but powerful worlds of the Warden Diamond.