Operation Sierra-75 is the sixth book in the series based on the game Vor: the Maelstrom which posits the Earth and its moon torn from the solar system and deposited in the Maelstrom, a force which has trapped many other planets as well. In this title, a survey team sent to explore another planet disappears, and the powers that be call in the Marines to accompany a rescue team. When they get to the planet, they find abandoned ruins and experience curious phenomena. Finally, they encounter humanoid alien forms which they call Mashers for their ability to "mash" inorganic material into their flesh.

The challenge presented to me as a reader was twofold: would I be able to follow the story without having read the previous novels, and would the book hold my interest, since it was not the kind of book I pick up typically. Gressman does a very good job with back story, incorporating it skillfully into the narrative. I knew enough to grasp the situation, and I appreciated being spared pages of exposition or worse, pages of expository dialogue.

The first chapter or so was slow going until the rescue ship arrives at the planet, but the plot picks up considerably from there and in fact, had me reading far into the night, determined to finish it. Gressman has a strong narrative style that hooks you in and keeps you guessing and turning the pages, just to see what happens next.

Granted, there is little or no characterization. We are presumably supposed to identify with Captain Max Taggart and gunnery sergeant Owana Frost, but they are stiff flat characters who demonstrate little more than concern that their superior status as Marines be held in the highest regard at all times by everyone. Furthermore, that status seems to exempt them from demonstrating respect for any non-Marine in the vicinity. Rebecca Cortez, the doctor leading the medical team, is intended to be the antagonist -- she's a naval officer and hence entitled only to scorn from the Marines -- but Taggart and Frost's attitudes make her much more sympathetic. Gressman is far more successful with his scouts, Dade and Black; I would be inclined to pick up a novel featuring them.

The plot, while gripping, does have flaws. Nothing is really resolved at the end, and no understanding of the Mashers is provided, apart from their being ugly, strong, smelly and inclined toward sneak attacks. Loose threads are not tied up, which is not a requirement, but not enough resolution is given to the reader to allow him or her to ponder possible outcomes.

Still, for a space adventure and escape reading, Operation Sierra-75 is a good bet, especially if you play the game or are interested in this sub-genre of science fiction.