Tim Zahn is an unusual author. He can write fast-moving, well-written adventures without gratuitous sex or foul language. How does he do it? Angelmass is a good example. What is it about?
A highly unusual black hole near an ex-Earth colony group called the Empyrean has been emitting impossible particles. The particles are called angels because they appear to encourage their wearers to do good. Fearing that these angels are actually an alien invasion, the forces of Earth, called Pax, prepare to invade, first sending scientist Jereko Kosta to investigate.
With little more than a few weeks of preparation and an entirely paper background, Kosta has little chance to succeed, especially when he becomes involved with teen-age grifter Chandris Lalasha. Chandris is running for her life, but sees a chance to get a berth on an angel-search ship as an opportunity both to lay low, and to score the biggest score of her life. She can't figure Kosta out. Somehow, he doesn't fit into any of the categories and this makes her nervous.
Despite political pressures, Kosta begins to discover secrets about the angels that neither Pax nor the humans of the Angel's own system suspect. Whether the angels are, truly, quanta of good as some believe, or somehow intelligent themselves, they have a definite impact on the people they come in contact with. Fortunately for Kosta, one impact seems to be that they become almost criminally lax in their security.
Kosta was sent out as a trojan horse, supposedly easy to capture. Instead, he manages to dig deeper than anyone had expected becoming an unlikely hero. The speculation on the Angels, and the mystery that they pose, is well handled both from a scientific and from a mythical standpoint. Zahn makes you think about what makes people tick.
The three main characters, Kosta, Chandris, and High Senator Forsythe of the Empyrean are well drawn and important to the philosophical underpinnings of the tale. The story could have been more densely textured, but as it is, it makes one think, as it moves along at quite a rapid pace.