Robert A. Heinlein was the greatest science fiction writer who ever lived. His novels have been translated into every literate language on the globe—over 25 million Heinlein books are in print in this country alone. For five decades, young readers of science fiction discovered Heinlein, then gone on to voraciously devour every Heinlein book they can get their hands on. His now-legendary Stranger in a Strange Land was the first hardcover bestseller by a science fiction writer. From 1975 on, every new Heinlein novel made the New York Times best-seller list and shipped a million copies, including The Number of the Beast, Friday, Job: A Comedy of Justice, The Cat Who Walks Through Walls, and To Sail Beyond the Sunset. In a career spanning half a century, he wrote over forty books, and four of his novels won Hugo Awards, an unequalled record for almost four decades. For the last three generations of readers, Heinlein is science fiction.

First came the news that a flying saucer had landed in Iowa. Then came the announcement that the whole thing was a hoax. End of story. Case closed. Except that two agents of the most secret intelligence agency in the U.S. government were on the scene and disappeared without reporting in. And four more agents who were sent in also disappeared. So the head of the agency and his two top agents went in and managed to get out with their discovery: an invasion is underway by slug-like aliens who can touch a human and completely control his or her mind. Sam Cavanaugh was one of the agents who discovered the truth. Unfortunately, that was just before he was taken over by one of the aliens and began working for the invaders, with no will of his own. And he has just learned that a high official in the Treasury Department is now under control of the aliens. Since the Treasury Department includes the Secret Service, which safeguards the President of the United States, control of the entire nation is near at hand...