A BOAT OFF THE COAST By Stephen Dobyns Viking. 260 pp. $16.95

If the Hardy Boys were to contemplate one of their cases through a cloud of pot smoke, they could cause no more shock to their fans than will shake faithful readers of Stephen Dobyns' Saratoga-based detective stories when they dip into his newest work, "A Boat off the Coast."

Followers of Charlie Bradshaw, Dobyns' spa private eye, know him to be a kind and decent man whose moral code would fit snugly over the body of a bishop, and when told that the coast off which the boat lurks is that of Maine, Dobyns devotees will expect some homely philosophy and a nice clean murder with a minimum of blood.

What they get is a cast of characters as seedy as any since the curtain rose on Gogol's "Lower Depths" and a rattle of violent action fueled by the drive to earn big money with cocaine.

Under all the gut-punching, however, there are character examinations that give us an interest in the protagonists far beyond the simple concerns about who will make the delivery and get the money.

At Belfast High, Tucker Morgan had been the leader and Brian Davis the "hey-wait-for-me" acolyte, and their reunion, nearly 20 years later, starts the unwinding of the spring that moves the book along.

Tucker explains himself to Brian's sister-in-law by saying, "You grow up and play pretty fair and think you're a pretty good kid and you hate the bullies and the cheats. Then you go someplace and suddenly you're the bully and the cheat."

We meet Tucker in a pointless bar fight and Brian at his nasty job in a chicken slaughterhouse. They are a couple of American dreams turned sour, the Hero and the Hard Worker. In their Belfast football days, life was as simple as Tucker passing and Brian catching -- a touchdown, a triumph, a total meshing of talents. When their gears come together again it is to move a machine in a darker direction, a direction masked from Brian at least by the residual effects of his boyish loyalties.

Dobyns shows us in gritty detail a Maine that would put pallor on the ruddy cheeks of Joseph C. Lincoln's Down Easters. Tourists are shadowy figures in the background of a place that seems to be littered with the ugliness of broken machinery and broken hopes.

The big weekend fun in Belfast appears to be a mock war fought with air guns firing paint pellets, a release of frustration through the infliction of humiliation, and a chance to get away from small lives into a world that begins to expand with the broaching of the second six-pack and the planting of a red splash on the heart of a temporary enemy.

The central figure in the story is Tucker Morgan, and we are given a number of trips through his mind, which shifts its perspectives to current needs in approved psychopathic fashion, but gives us the softening effect of Tucker's eloquent self-justification. One is reminded of H.G. Wells' "Bulpington of Blup," a pathological liar who, after a particularly fantastic whopper, broods on its total sham and then shrugs away his guilt with the thought that if it wasn't true, by God it ought to be true.

Early on in "A Boat off the Coast" there was more about the operation of a chicken slaughterhouse than I wanted to know, and near the end there was a bit more punching and kicking than I wanted to read, but the whole structure is as sound as a Maine fishing trawler, and the result is a satisfying piece of work.

Here is none of the cookie-cutter idiosyncrasy of the crime story writer who, having created an acceptable eccentric protagonist, changes plots but not setting. I don't even know if "A Boat off the Coast" is a crime story or a novel of character. I don't know if Charlie Bradshaw, reading it, would much care for it. It is, however, an interesting new direction for Stephen Dobyns and it will be fascinating to see whether, in his next book, he returns to the coffee and doughnut comfort of Bradshaw's Saratoga, stays on the wretched rock-bound shores of Maine, or takes us perhaps to a suite overlooking the sea in Monte Carlo. The reviewer is the author of a memoir, "Whose Little Boy Are You?," and the novel "A Studied Madness.