Shooting star cut by Madonna

The careers of the British New Wave directors, launched with a fanfare of vitality and freshness in the late 1950s, offer a uniformly sad spectacle of inexorable decline. Lindsay Anderson, Tony Richardson, Karel Reisz and Jack Clayton all saw their early promise drain into a morass of potboiling projects, often further compromised by Hollywood studio interference. The journey from This Sporting Life to The Whales of August , or from A Taste of Honey to The Hotel New Hampshire , seems a depressingly downhill road.

In some ways, John Schlesinger lasted better than his colleagues. Not until the late 1970s, after the critical and commercial success of Marathon Man , did his career go seriously off the rails; and as late as 1991 he was still capable of such subtle, perceptive work as the Alan Bennett-scripted A Question of Attribution , even if he had to retreat to his first home, BBC Television, to make it. But his last few cinematic excursions offer all the grisly fascination of a motorway pile-up. On his final film, a dire comedy with Rupert Everett and Madonna hopefully titled The Next Best Thing , the veteran director suffered the indignity of being told by Madonna that he "didn't know what he was talking about". In former years, as William J. Mann observes, such impertinence would have elicited from Schlesinger a roar that "would have shorted out the amps". But he was now 73, sick, weary and despondent. "My dear," he told an assistant, "I just couldn't be bothered."

Mann gives us this glum Portrait of the Artist in Extremis in his opening chapter, prefacing it with Schlesinger's career highpoint 30 years earlier, the night of the Academy Awards in 1970 when Midnight Cowboy brought him the Oscar for Best Director. Not long after the release of The Next Best Thing , Schlesinger suffered a stroke that left him immobile and near speechless for the last 30 months of his life. It was then that Mann embarked on his biography, and his narrative returns repeatedly to the slumped figure of Schlesinger in his wheelchair. But by reminding us so insistently of the debilitating effects of the stroke, he robs the event of its full emotional impact.

Mann is gay, as was Schlesinger, and he gives a sympathetic and sensitive account of the director's emotional life. His social life, too, comes in for plenty of attention; one or two chapters degenerate into little more than awed enumeration of the A-list celebrities who graced the parties at Schlesinger's Hollywood Hills mansion. All this is sometimes at the expense of the films, about which Mann has little new to say. He hails Sunday, Bloody Sunday as "Schlesinger's masterpiece" (it is certainly his most personal and deeply felt film, which is not necessarily quite the same thing), and joins the conventional view in his grudging account of Far from the Madding Crowd , which, for all its faults, still looks like the best fist anyone has yet made of the near-impossible task of filming Thomas Hardy. There are valiant attempts to put in a good word for some of Schlesinger's more ambitious flops, such as The Day of the Locust , Yanks and even the sprawling comedy that all but put paid to its director's career, Honky Tonk Freeway .

For obvious reasons, Mann was able to glean only limited material directly from his subject, relying instead on input from friends, family and colleagues, on Schlesinger's previously published interviews and his extensive tape-recorded diaries. The book is strong on the film-maker's early years, his upbringing in a liberal, cultured Hampstead Jewish family that nonetheless left him with a pervasive sense of never being "quite good enough", and his formative period under mentors such as Donald Baverstock and Huw Wheldon at the BBC, where he explored the social realism that fed into his debut feature, A Kind of Loving . The inferiority complex surfaced again with other New Wave directors. Schlesinger, says Mann, felt he "could never compete with the intellectual sparring of colleagues such as Anderson and Reisz" - who patronised him for making box-office hits such as Darling and Midnight Cowboy .

This attitude often extended to the critics; as Mann notes, Schlesinger was the most commercially successful of the leading New Wave directors, but the least critically acclaimed. Since his death, his reputation has shown little sign of recovery, and Mann's book, detailed and appreciative though it is, seems unlikely to change this.

Philip Kemp is a freelance writer on film.