By Robert Reeves

Crown. 244 pp. $18.95

The rights to produce and to consume pornography, and the desire by many to protect society from pornography's pernicious effects, tie a durable knot of legal and social issues in this country. It's a conundrum with plenty of paradoxes and ironies, such as the momentary alignments of radical feminists with moral majority crusaders on the one hand and civil rights groups with smut peddlers on the other. To plot a mystery novel through this set of issues, while doing justice to their complexities, is a tall order.

But that is what Robert Reeves has done in "Peeping Thomas," which takes the novel's narrator, Wesley College English professor Thomas Theron (hero of Reeves's first novel, "Doubting Thomas"), and places him in the dangerous role of bumbling, do-good investigator into the bombing of a porn shop called the First Amendment in Boston's Combat Zone. The professor, an aspiring novelist with a history of slumming it, teams up with his ex-wife and a former professional wrestler to rescue a missing sex starlet, known to her admirers as Sheena Sands, and to solve the murder of Emma Pierce, a feminist historian at Wesley, who dies in the bombing.

Theron's descent into the now-shrinking Combat Zone comes when he receives an early morning phone call from Pierce seeking his aid in picketing the porn shops. He halfheartedly complies, and just after Pierce hands him a videotape featuring the alluring Sheena Sands, sent to Pierce by a student, a bomb goes off in the store. Soon it's clear that the anti-pornography demonstrators are not to blame, and that others, perhaps pornographers themselves, are responsible. Theron, caught in the media coverage of the bombing, must now clear his name, and his adventures in the Boston skin trade lead him to ever-higher levels of corporate and governmental intrigue.

As a thriller, "Peeping Thomas" depends upon such propitious events as new characters popping up with crucial information that advances Theron's investigation. These plot movements are lubricated by the professor saying such things as, "At least we'd have a place to start asking questions, and if we asked enough questions, maybe we'd get lucky." Yes indeed. They get too lucky too often, their breaks in the investigation coming without the authentic connective tissue of causation that a plausible thriller requires. That said, "Peeping Thomas" is swiftly economical in finding its way to all the places the reader wants it to go: the strip joint, the evil yuppie pornographer's home, the set where porn movies are made, the corporate mogul's office etc.

Reeves's more certain strength is his eye for detail and the voice of Theron, who possesses a likable cynicism: "At best, I supposed, a dog race offered a perverse metaphor for life: all the contestants looked the same, it was over before you knew it, and you couldn't make much sense of what had happened." Theron is unrelenting when describing the tortuous political infighting that occurs at a departmental faculty meeting. His older colleagues "might have been on a weekend pass from an elitist nursing home." In fact, a faculty inquiry into Theron's questionable activities is stopped cold by a sudden demented rant on Victorian sexual practices by the department's "great addled genius."

Such momentary lightheartedness doesn't inhibit Reeves from a deeper, more serious examination of pornography; he provides a full palette of attitudes on the subject. Speaking about the proliferation of pornographic tapes in neighborhood video stores around the country, Emma Pierce says, "What if there were an aisle where the Ku Klux Klan could rent movies about humiliating black men, or Nazis would rent movies depicting the torturing of Jews? No one would stand for it. ... This isn't a free-speech issue. {It} isn't about sex. What it's about is the wholesale promotion of hatred of women, hatred that promotes violence."

Pierce's righteous anger is counterbalanced by Theron's own ambivalent interest in pornography -- his acknowledgment of "that secret gallery ... the obscene stash of the mind's eye" -- and by the jaded comments of Byron Choate, the novel's pornographer: "Every feminist knows in her heart that copulation isn't equal or progressive. ... Men mount women and penetrate them, and there's no getting around it. That's the one thing you can't finesse in a porn film ... No amount of social engineering can redeem it. An image of a piston shot has been seared into our brains; it informs our lives, our very language."

Such an observation, whether correct or not, provides an intellectual edge not often present in mysteries, and for readers willing to explore these gritty regions, "Peeping Thomas" is intriguing. To use the author's words when describing the photographic wares of the porn shop, the focus here is "sharp enough to make you wince."

The reviewer is the author of the novel "Break and Enter."