OSS story: shattering failures and shadowy victories; The Last Hero: Wild Bill Donovan, by Anthony Cave Brown. New York: Times Books. 891 pp. $24.95.

The spate of books about the intelligence community in war and peace roars on. Back in 1975 Anthony Cave Brown made a notable contribution with ''Bodyguard of Lies,'' which focused on the use of deception in World War II. Now, after five years of formidable research, he gives us a volume which could easily have been called ''Bodyguard of Spies,'' so kindred is it in spirit and execution.

Brown builds his story of the Office of Strategic Services (OSS), 1941-46, around the complex figure of Maj. Gen. William J. Donovan, founding head of the organization and chief mover and shaker during its short, tumultuous existence. Even Donovan's nickname, ''Wild Bill'' (which stemmed from the World War I heroism that earned him the Medal of Honor) seems a contradiction, for he was soft of speech and there was a deceptive mildness to his light blue eyes.

''You have to remember,'' a senior veteran of the OSS said to me the other day, ''that our record was extremely uneven. Much as I admired him, so was the General's.'' It is to Brown's credit that he keeps his strong case of hero worship firmly under control, and that he touches on some of the shattering failures as well as the shadowy victories. There are times, as the hurtling action unfolds, when Donovan comes on stage mechanically like one of those figures in a Swiss barometer, then goes off again. We glimpse him munching an apple during the D-Day landings, staging secret behind-the-lines meetings in Italy and Burma. Yet the cumulative effect of such writing is impressive, for Brown does manage to scoop up a good deal of the magic of the man whom Eisenhower called ''the last hero.'' In the end we share the admiration and the awe that enveloped him.

Brown makes a good deal of the fact that he is the first writer to have access to Donovan's secret papers and to the diaries of his wife, Ruth, fated to be on the sidelines a good deal of the time. He also reminds us that there were several false starts on a major biography - by Cornelius Ryan and others - before Brown tackled the huge task. What he doesn't quite say is that one of his predecessors, Corey Ford, actually did publish an affectionate memoir, ''Donovan of the OSS,'' back in 1970.

There will be others to come. Even though the personal papers Brown relies on so largely tend to give a kind of tunnel vision, he has nonetheless written a blockbuster of a book, and one in which the reader's interest will seldom flag.

Here are some of the highlights:

* Donovan's offer of $1 million to a German diplomat if he would cooperate in killing Hitler.

* Donovan's relationship with British Intelligence in general, and with the legendary man called Intrepid in particular.

* The splendid concept of the Arcadia Plan to set captive Europe ablaze from within.

* The strange role that Donovan and one of his agents played in the death of Admiral Darlan.

* OSS operations in Italy, Greece, Burma, and elsewhere - uneven in results, but all bearing the mark of Donovan's leadership.

A most absorbing chapter is the account of a palace revolt in Washington against what was inevitably becoming something of a one-man show. Several senior executives proposed that Donovan be kicked upstairs to chairman and that the OSS be run more like a bank. One can almost see the Donovan eye turn a paler blue and the voice go softer than usual as he comments:

''The OSS is not a bank and should not be run as a bank. It is not a War Department and should not be run as that. . . . It is made up of a diversity of units and while certain fundamental principles must be kept in mind the whole organization must be a flexible one to meet any particular ends, and so long as I have anything to say about it, it is not going to be wed to any particular scheme or put in any particular niche.''

There is sadness at the end. President Truman dissolved the OSS. Donovan's own last years were laced with tragedy. But out of his pioneer work came America's permanent intelligence apparat. And Donovan's own life was unquestionably a fascinating example of American ingenuity and valor in the service of his country.