DEATH IS A LONELY BUSINESS. By Ray Bradbury. Knopf. 279 pp. $15.95.

VENICE. 1950. Venice, California. Not Italy. Not Florida. There is wet sand on the beach. And evil fog. And there are foghorns that moan like a brontosaurus with bronchitis. There is an old dead man in the green-scummed canal. There is a detective with a secret, perhaps unspeakable, vice. The detective's name is Elmo Crumley.

Crumley is tough and cynical and hardboiled, except at the core where he is as soft and gooey as a marshmallow toasted over a driftwood fire.

But Crumley is not our hero. He is our hero's new best friend. Our hero is a Young Writer. He writes for the pulps -- for Weird Tales and Amazing Stories -- and hopes, one suspects, to sell something eventually to Street & Smith's classy Unknown, which by 1950 was called Unknown Worlds.

But weren't the pulps dead by 1950? Killed off by television? Murdered? Or was that later? Memory fails. Ray Bradbury says they were still alive and he is an authority. One should trust authority. He also says haircuts were $2 in 1950. I thought they were less. Perhaps they were in the barber college -- the one just off Canal Street in New Orleans. Phone calls cost a nickel then in New Orleans. I'm told they still do. I'm told Huey Long wrote it into the state constitution in 1933. Or was it '32? A good 5-cent phone call. Some things wonderful and fine endure.

Comes now the fey part. For this is a very fey murder mystery. Loveable, cranky, crusty, wisecracking characters abound. And our fey Young Writer is always with us, too, screaming out the window to all the world that he has just sold a story to The American Mercury; dashing across the street to answer the pay phone; riding the big red streetcars late at night; typing happily away -- and rapidly, one suspects -- on his 1935 typewriter.

But if you grow a bit tired of fey, how about a slice of quaint? There is a possible villain who has the body of a gorgeous young boy and the face of an evil old man. There is a blind man who grows rich betting on horses he can't see -- although that may be more fey than quaint. There is an aging silent movie screen goddess who goes about in her Duesenberg disguised as her own chauffeur. There is an incompetent barber who once played with Scott Joplin. And there are a lot of dead and not overly interesting victims who for the most part die off stage.

BUT IF neither fey nor quaint is your dish, what about sentimentality? For this is a very long and sentimental mystery. Our Young Writer hero's eyes mist over when they tear down the old beach motion picture house. The razing of the Venice rollercoaster makes him mourn. He consoles himself with candy bars, casting the wrappers carelessly away on the beach, which is about where the knowledgeable reader will say to himself: "Aha! A clue! A clue!"

But the death toll continues to mount and there is none to believe the Young Writer's claim that something sinister is afoot. This is because all of the deaths are apparently from natural causes! Yet he believes. He senses. He feels. And he detects. God, how he detects. And finally, at long, long last, the murderer is revealed.

Ray Bradbury's writing remains as rich and ripe as ever. When describing a woman he has his Young Writer hero think of her as being "a lovely chess game carved and set in a store window when you were a kid. She was a freshly built girl's gym, with only the faintest scent of the noon tennis dust that clings to golden thighs."

And on writing itself, our Young Writer hero is convinced that "A day without writing was a little death . . . I would fight all the way with my Remington portable which shoots more squarely, if you aim it right, than the rifle of the same name."

As for the secret, unspeakable vice that has Detective Elmo Crumley in its thrall -- well, he's a closet novelist.

Ray Bradbury has dedicated this novel, his first since Something Wicked This Way Comes, to -- among others -- Raymond Chandler, Dashiell Hammett, James M. Cain, and Ross Macdonald.

I am confident that each in his own way would have read it with deep interest.