Nerve of Steel : VIOLENT WARD, <i> By Len Deighton (HarperCollins: $23; 305 pp.)</i>

During the Cold War things were simpler. Len Deighton’s master spy Bernard Samson marked the halfway point between Ian Fleming’s James Bond and John Le Carre’s cerebral George Smiley. With Deighton maybe you couldn’t quite figure out the plot but at least the secret agents had guns. But with the razing of the Berlin Wall in 1989 ( annus horribilis for espionage writers), everything changed. Now John Le Carre writes about drugs-for-arms deals in Curacao and Len Deighton has taken literary refuge in, of all places, Los Angeles.

Deighton, who has had a long and distinguished career moving spies in and out of enemy lines, tries out a new and more humble protagonist here: Mickey Murphy, a criminal lawyer working out of a rundown office near South Central L.A. Murphy’s law firm functions according to Murphy’s Law. Murphy has two Asian partners, one of whom has a sideline in obtaining for living clients fake death certificates. He gets hit by an RV; his colleague has a heart attack. Murphy’s ex-wife Betty, who in the book’s first scene stands on his window ledge threatening suicide, winds up a successful Hollywood agent.

Murphy struggles to keep up with these events. His character owes more than a small debt to Philip Marlowe; an ex-marine in love with his 1959 Cadillac, Murphy has an approach to criminal law that relies more on breaking-and-entering than cross-examination. He notes with satisfaction that the government “could have had me disbarred a dozen times over.” He knows how to brawl, wipe a crime scene clean of his fingerprints and stay cool even when the phone he picks up is wired to a bomb.

Steely nerves turn out to be a special plus when his law firm’s new partner comes to town. This is none other than Zach Petrovich, head of Petrovich Enterprises International, a.k.a. “el supremo, ichi-ban, tycoon extraordinaire.” Petrovich is a man “as crooked as you can get without ski masks and sawed-off shotguns”--and he also happens to be married to Ingrid, Murphy’s high school sweetheart.

The plot centers on whether in the midst of some tax shelter shenanigans Petrovich is trying to kill Ingrid or Ingrid trying to kill him. The answer isn’t hard to come up with if you know your noir . If not, perhaps the scene in which Ingrid pleads with Murphy will help (imagine Mary Astor and Humphrey Bogart):

“ ‘I didn’t want to get you involved, Mickey. I really didn’t. But there’s no one else I can turn to. . . . I think I’m in danger.’ She reached out and touched my hand, and just that light physical contact made me shiver.

“ ‘Danger how?’

“ ‘I can’t explain . . . not now.’ ”

Does Deighton want to send up hard-boiled thrillers or write one? “Violent Ward” packs little energy: Anyone could have planted the phone bomb and anyone could have done away with Mr. Pindero, a minor character who is introduced largely for that purpose. “Petrovich doesn’t finalize deals. He finalizes people,” Pindero red-herrings before meeting his fate.

The book is full of improbable turns, surprising from a writer as expert as Deighton. Trying to erase evidence he has been at Pindero’s house, Murphy explains he took his vintage Cadillac to a car wash in the middle of a rainstorm in order not to attract attention. A joke about the Cadillac leaking oil has no pay-off. A girlfriend introduced halfway through the book never appears again and is never mentioned when Murphy reunites with Betty.

Murphy himself is a mass of inconsistencies. He’s supposed to be Southern California born and bred but sounds more like Lord Peter Wimsey than Sam Spade. He “posts” his mail, calls football players “footballers,” and, giving the once-over to Pindero’s house, asks: “Why did a guy leave so hurriedly that he didn’t even grab his soap and razor?”

The backdrop for “Violent Ward” are the riots following the Rodney King verdict, about which Deighton seems to want to make an editorial point: “Like most of the city’s inhabitants, I spent many of those early hours of the riots comparing the TV coverage with wary glances out the window, until eventually I could hardly distinguish between those two distorting sheets of glass. . . . Is it television, is it reality or is it neither?”

Or is it Marshall McLuhan?