Black comedy from an old smoothie; Doctor Fischer of Geneva, or The Bomb Party, by Graham Greene. New York: Simon & Schuster. $9.95

Graham Greene's latest novel is a comedy of manners. Bad manners. Its protagonist, Dr. Fischer, doesn't throw bombs. He throws bomb parties. Dr. Fischer is rich -- a fortune made in toothpaste -- and he has expensive tastes. That is, he likes caviar and good wines. He also gives expensive presents: necklaces hung with Krugerrands, platinum cigar cutters, "eighteen-karat-gold watches -- quartz watches with computers and all the works." Bagatelles like that.

You'd like to meet Dr. Fischer and be invited to his bomb parties? But beware. Dr. Fischer, like Lord Byron, is mad, bad, and dangerous to know. He makes you pay for your parties and your presents. First of all, you must be rich. Second, you must be greedy. Third, you must grovel.

Dr. Fischer, you see, despises that unfeathered biped known as man. And to confirm man's despicability, Dr. Fischer surrounds himself with "Toads" or toadies. Toads of the vulgar sort: falling movie stars, an international tax lawyer with a sharp eye for loopholes, an American widow with blue hair. No, these are not Dr. Fischer's friends. He invites them to parties to humiliate them. To see how much they will put up with. Sample humiliation:

"There was one evening -- can you believe it? -- he served up live lobsters with bowls of boiling water. We had to catch and cook our own. One lobster nipped the General's finger. -- I bear the scar still, Divisionnaire Kreuger complained. -- The only wound in action which he ever received, Doctor Fischer said."

Graham Greene calls this sort of novel an entertainment. This one is billed as a "black entertainment." That's because Dr. Fischer is an experimenter in human greed. Will his guests bear his insults to get his presents?

There is a love story running through this entertainment. Sweet and sad, the way Erich Segal also likes to tell them. And there is a lot of fashionable flak about Mozart on cassette, Swiss chocolate laced with whiskey, gold swizzle sticks, ski slopes called pistesm and color-coded for difficulty.

Like his predecessor in this genre, Somerset Maugham, Greene is an old smoothie, a real pro, and if you're willing to suspend your disbelief in just about everything you know, he will provide you with a couple hours of diversion. Don't ask for more, and you won't be too disappointed when the bomb party bombs.