It was a desperate move that cost him literally an arm and a leg, so that he could carry a warning of a deadly invasion force making its way towards Chilo, from which no human would be safe. One by one the passengers and crew of the ship he had been traveling on had succumbed to the infection that turned them into mindless extensions of a collective consciousness known as The Swarm. Instead of killing those who stood in their way, The Swarm was more interested in making everybody one of them by spreading the infection through the simple expedient of biting their potential victims.

At first it's thought that Chilo was only a random target, but Pepper finds out information about the city of Yatapek that makes him question that assumption. The city depends on what little precious metal it can excavate from beneath the surface of the planet for its survival. Centuries ago when it was founded, the original colonists had purchased protective suits that allowed people to walk on the surface for short periods of time. Over the years the suits had worn down and the city couldn't afford the technology to repair them - let alone upgrade them. The only people able to fit in the suits anymore are teenagers willing to starve themselves to maintain a small enough stature to fit in them.

On the day Pepper fell through the atmosphere, Timas was walking the surface in an attempt to gauge the extent of the damage that the debris from Pepper's forced entry caused the drilling apparatus. While out there he swears he saw other life forms moving across the surface. While nobody else believes him, when he tells Pepper, the Mongoose Man thinks he sees a reason for the invasion. What if there are survivors of the former overlords somehow living on the planet's surface and the League has created this "infection" as a means to eliminate them?

With Sly Mongoose, Tobias Buckell has taken your standard space action adventure story and given it a little extra bite with the addition of a zombie army seemingly intent on replicating itself until it swallows all of humanity. While the story line is pretty much as old as the genre (a mysterious alien threat), Buckell's ability to create interesting characters keeps the book from descending to the level of a cliche. While at first glance Pepper appears to be nothing more than a standard action hero, he's gradually revealed to be a far more complicated and interesting character than your average killing machine.