When I was in the ninth grade I joined the Science Fiction Book Club and got my first five books for a dollar. One of those books was called “A Heinlein Trio” and the first of the stories was “The Puppet Masters” by Robert Heinlein. It was the second Heinlein book I read (the first was “Between Planets” which was serialized as a comic book in “Boy’s Life” magazine) and it’s a great example of Heinlein writing exciting stories built on themes he cared strongly about—the importance of the individual and the dangers of a society in which all members are expected to tow the same political and ideological line regardless of their self-interests and personal philosophies. Heinlein published “The Puppet Masters” in 1951 after a rash of UFO sightings in the 1940s. Heinlein used the sightings as a springboard for an imaginative and disturbing tale of slug-like creatures capable of taking over the minds of any human (and many other creatures) that they touch. The enslaved human knows what it is doing, but lacks even the desire (much less the ability) to fight against the alien puppeteer. Heinlein’s novel takes the struggle against the alien invaders from first contact, to insidious infiltration, to widespread invasion and finally to the epic struggle to free our planet in an exciting adventure story. Yet, as important and entertaining as these events are, they are not what make the novel great. Instead it is the exploration—never preachy—into why freedom of conscious is important as well as the fundamental relationships which make human life worth living that give this book its power.As you would expect of a book written in the fifties, there is a dated feel to some elements of the book. For example, while Mary, Heinlein’s heroine, is definitely an empowered and capable woman, many of her reactions and the condescending way in which she is often treated, will grate irritatingly on the modern reader. Similarly, Heinlein’s vision of the late twenty-first century quite understandably fails to foretell many things we take for granted in modern life even while he foresees the growing importance of industries such as telecommunications. These faults don’t harm the story if you keep in mind when the tale was written. I highly recommend this book. 5 stars. Heinlein's books always seem to be hit or miss (compare the excellent The Moon is a Harsh Mistress with the mediocre Cat Who Walks Through Walls). This one, although the first third was quite good, is a miss. I enjoyed (but don't agree of course with) Heinlein's dated attitudes about women, the Iron Curtain, etc., but the promising start of the book faded to a disappointingly boring conclusion. It's like Heinlein had a rough idea for a book, got a short deadline, and then typed away until it was done. I haven't thought of this before, but I wonder whether this book suffered from the lack of word processing, where revisions and editing are light years simpler.