Ah, journalists! the new literati, masters of the electronic karate chop and the wry Manhattan. For 20 years they -- the best, the brightest and the brashest -- have been moving from behind The Front Page onto it, and nowhere are these purveyors of clauses celebres so prominent as at Elaine's.

Now Elaine's, the trendy writer's hangout, is the scene of a tongue-in-chic entertainment which ecumenically mixes blackmail, drugs and dirty tricks into a kind of "All the President's Men Meet the Vontinental Op on Second Avenue."

Although the title represents this as a murder mystery, it's really more of a fantasized Rolling Stone investigation into some still unexplained pieces of the Wathergate jigsaw. A magazine-publishing mogul, whose fall from prwer (epitomized by the loss of "his" table at Elaine's) has set him aflame with the desire for revenge, is murdered amidst the creme de la creme as their chauffeurs toke in the parking lot. His beautiful compainion, a sometime bigtime drugrunner who has chewed up and spit out her banana-republic-tupe husband, goes on the lam to her friend the opium-smoking gonzo journalist. Then the crazy medical examiner finds tose missing 18 munutes in the morgue....

In case you think Rosenbaum has trod ginerly down madia byways, you can relax in the knowledge that he has studded the text with references to George Plimpton, Mary Jo Kopechne, Tony Ulasiewicz, Bob Dylan, Gael Greene, Swifty, Mica, and so forth. And if the murdered magazine publisher sounds a little like Clay Felker, and the narrator a lot like Hunter Thompson, the more the merrier.

The tone of the piece is well set by the Roy Lich-tenstein-style cover and the back-cover diagram of the "floor plan of Elaine's with hostility vectors." (Stonehill, $7.95)