Gruesome, Gory and Gratuitous : GAMES OF THE HANGMAN, <i> By Victor O’Reilly (Grove Weidenfeld: $19.95; 516 pp.)</i>

Remember those days of derring-do when British Secret Service Agent 007, James Bond, chased cartoon villains such as Dr. No, Goldfinger and the estimable Pussy Galore? Ian Fleming, author of the Bond novels, is generally acknowledged as the founding father of the spy thriller, and the intensity of Cold War politics gave his global battles of Good Vs. Evil a credible context. After all, if Khrushchev could bring the nuclear threat right into Havana Harbor as he did during the Cuban Missile Crisis, Fleming’s scenarios didn’t seem so far-fetched.

Nearly three decades after the height of 007’s popularity, the spy thriller has become a major fictional genre, and Fleming’s innovations have become conventions. As the genre developed, Robert Ludlum added lots of ingenious twists and turns to the chase, John le Carre plumbed the murky philosophical depths of life in espionage, and Tom Clancy brought us a dazzling array of new space-age weaponry. A broad range of other writers has experimented with the form. In fact, one of the major flaws of Norman Mailer’s self-proclaimed “existential thriller,” “Harlot’s Ghost,” is that he evoked the conventions of the spy thriller and then failed to pay off readers’ legitimate expectations.

In “Games of the Hangman,” Victor O’Reilly proves himself an eager student of Fleming, Ludlum and Clancy. Overeager, perhaps. This fast-moving story is jump-started when Hugo Fitzduane, ex-soldier of fortune and war photographer, discovers a body hanging from an oak tree on the grounds of his ancestral castle in Ireland. Although the authorities say that it was simply the suicide of a student from the nearby school for rich kids, Fitzduane’s instincts tell him otherwise. The trail leads from Dublin to Bern, Switzerland, where arch-criminal Felix Kadar has his headquarters.

Kadar, a.k.a. Balzac and the Hangman, is a Harvard MBA whose warped but brilliant mind has come up with a terrorism-for-profit scheme that entails subverting politically motivated terrorist groups into a monstrous army that will kidnap all the rich kids in the school near Fitzduane and hold them for multimillion-dollar ransoms. Better yet, Kadar also is an amoral beast whose insatiable bisexual lusts and violent psychopathology conjure up some scenes of sexual torture and murder worthy of Bret Easton Ellis.

Here’s the fiendish Kadar--who has already been chopping up the bodies of his bedtime playmates and executing disobedient terrorists with a flamethrower--talking to a beautiful young associate who is trembling and, of course, naked before him. He has just finished explaining, once again, his big-business theory of crime (“You see, I worked out my particular multinational management style, my objectives, and my strategy when I was at Harvard. It was while studying the activities of the big soap companies like Procter and Gamble and Unilever that I got the idea.” She doesn’t laugh because she’s bound and gagged. Then, with a gulp of brandy and a puff of his cigar, he gets around to why she’s sitting there with surgical tape wrapped over her mouth:

‘ “My dear darling Esther,’ he said, ‘you are going to be garotted. It’s a technique that was rather popular with the Spanish, I’m told. I think I’ve got the machinery right, though one cannot be sure without field testing. . . . They tell me that the physical result is similar to strangulation: your eyes will bulge, your face will turn blue, your tongue will stick out, and the force exerted by the screw on the back of your neck will break it. By then, I expect, you will be unconscious and either dead or close to it, so you’ll miss the final action. It’s a pity but that’s just the way it is.’ ”

You can practically hear them hissing from the cheap seats in the balcony as this incarnation of evil goes through his dastardly paces. Luckily, Fitzduane, with his faithful Swiss companion, Detective Sergeant First Class Heinz Raufman (a.k.a. the Bear), is a match for Kadar. After various explosive encounters between the two, Kadar finally invades Fitzduane’s island with his army of terrorists and a boatload of high-tech weaponry. Hugo and his smaller group of pals end up defending the Fitzduane medieval castle from a 21st-Century assault, and the ensuing battle scene is a technothriller delight.

This all adds up to a marvelous, cartoon-y movie script (with Sean Connery as Fitzduane and Roy Scheider as Kadar). How much you will enjoy this as a reading experience depends, quite literally, upon how much overkill you can stand. O’Reilly’s portraits of Fitzduane, Raufman and several other characters are full and convincing, and he plays with the contrasting national characteristics of the Irish and the Swiss with entertaining effect. Even his improbably dramatic plot is impressive. But I lose the ability to suspend disbelief when body parts start flying and O’Reilly revs up the gruesome, gratuitous violence to Stephen King level.

Despite these serious reservations about his first novel, I think O’Reilly is a writer to watch. If he can just control his enthusiasm for gory fun, he has the talent to conjure up engrossing spy sagas in the future.