Romulus Fights the Power : THE CAVEMAN’S VALENTINE, <i> By George Dawes Green (Warner Books: $19.95; 323 pp.)</i>

Mental illness is tricky. I have a manic-depressive friend who, while in a manic phase, passionately dug up two rows of shrubbery outside her apartment complex. The idea was to plant a community-based vegetable garden. “People should have a deeper investment in their surroundings,” she explained to the irate landlord. “We can all share real-life vegetables.”

The landlord, however, didn’t want real-life vegetables.

Although my friend’s actions were destructive and illegal, many people would see them as immensely satisfying, even heroic, in a one-woman-stands-against-the-machine kind of way. It can be difficult to resist romanticizing certain types of mental illness, particularly when the illness appears to give the person afflicted direct access to higher truths.

In his first novel, “The Caveman’s Valentine,” George Dawes Green sets so many potential traps for himself that you can almost feel the tension like coiled springs under every page. Not satisfied with writing a complex literary thriller that remains humorous while subtly attacking the excesses of our culture, Green dares to make his protagonist a clinically paranoid homeless man.

Romulus Ledbetter lives in a cave in New York’s Inwood Park. A former pianist, he now eats out of trash cans, watches an unplugged TV set and fights a never-ending war against Stuyvesant, his omnipotent nemesis. Stuyvesant controls all of society with nefarious Y-Rays and Z-Rays that he shoots out from the Chrysler Building. “Y-Rays were for helling over a place. Y-Rays were for crudely hewing out the forms of backed-up toilets and tax collectors and . . . the grey death gathering on the faces of subway straphangers.” Put very simply, Y-Rays cause oppression. Z-Rays are different: “this sheen on the Hudson . . . the smell of sex and the smell of a rich man’s fields after a rain shower . . . a new and wickeder radiance.” Z-Rays use materialism to seduce us.

Romulus fights the powerful rays with his angels. “Romulus could feel them now--they were astir inside his skull. The Seraphs of Divinity and Vengeance. He felt them fluttering their little wings like moths against the soft walls of his brain. He felt their fury rising.” The wonderful and tragic thing about Romulus is that, like my bush-pulling manic depressive friend, he is unbalanced; but he is also right.

Things might have continued pretty much the same in Romulus’ life if it weren’t for the frozen body he discovers outside his cave early one February morning: a homeless man named Scotty Gates. The police believe he died of natural causes. Romulus disagrees. Not only did he clearly see the murderer on his private television set, but Matthew Donofrio, a homeless man who was Scotty’s lover, tells Romulus that before he died, Scotty had been tortured for months by a well-known painter. There was a videotape and blackmail. Matthew is convinced the painter murdered Scotty, but Romulus knows who is really behind all of it: Stuyvesant, the man at the top.

Guided by his sense of morality to find Scotty’s killer, Romulus is forced to reconnect with mainstream society. This isn’t easy for someone who has a brain full of angels, wears a saucepan lined with squirrel fur on his head and is prone to uncontrollable fits of rage. Here’s Romulus working a VCR: “Using his dim memory of the Bible for his instruction manual, he decided that Power was surely the prime mover, the essential beginning of things. He pushed. The machine sprang to attention. He fed it the tape, which it devoured.

“Now what? Why, we’re all the frolicking children of Eden, what else should we do but Play?”

For the most part “The Caveman’s Valentine” is nothing short of brilliant. Romulus’ character is so compelling that many readers will want to tear him from the page just to offer him a home-cooked dinner--no small feat, considering the man stinks and will shout obscenities without warning. Even more unusual is Green’s ability to remain scrupulously honest. Untrapped. Until the last 50 pages there is nothing glorified, polemical or cute about Romulus and the life he’s chosen. One example of this is a scene in North Carolina where Romulus, who is black, removes a Confederate flag from a motel lobby wall and sneaks it into the bottom of the racist proprietor’s bird cage.

Confronted with a scene like this, many authors would slow way down and possibly mention it again later--just to be sure we all understand that Big Issues are at play here. Instead, Green gives us a quick, funny throw-away that renders the section twice as effective. His presence as a writer is invisible.

Unfortunately there are some problems in the book. Toward the end, many characters change radically but with no clear provocation. One man goes from being a sarcastic jerk to a completely decent person in a very short span of time, while another metamorphoses into a towering, two-dimensional villain with no power or complexity. That would be fine in a lesser novel, but “The Caveman’s Valentine” is too smart for its standard thriller ending. Even Romulus changes. Perhaps an expert on clinical paranoia would disagree, but it strains credibility to think anyone who spends his time dodging greenish Z-Rays could truly move forward without considerable help.

In spite of its flaws, though, “The Caveman’s Valentine” is a great read. Character, plot and style are braided so beautifully together that the whole book shines with its own wild light. The light of good writing. Or, as Romulus would say, “Divinity.”