Anthony Julius has been hired by Avram Grant after the former Chelsea first-team coach was sacked by the club. Julius, who has a reputation as a tough negotiator, first advised Grant on his £3.5 million-a-year contract last December when terms were being negotiated. Now he is going back to Peter Kenyon, Chelsea’s chief executive, to try to secure a better severance deal. Grant, insiders say, is looking for every penny he can get.

“There are much easier ways of killing Jews. As the Foreign Office said in 1943, the gas chambers story seems absurd. What was wrong with the good old-fashioned bullet?”

Hearing these words clinically disgorged over lunch, I felt nauseous. My Sunday Times interviewee was David Irving, the odious Holocaust denier. He then launched a diatribe, worthy of Der Stürmer, against Anthony Julius, the Mischon de Reya lawyer who had helped to defeat his 2000 libel action against Deborah Lipstadt and Penguin Books. Shortly after our lunch, Irving spent 11 months in an Austrian jail for publicly denying the Holocaust.

Interviewing Julius is distinctly more agreeable than breaking bread with Irving. His expansive vocabulary, calibrated thinking and an impeccable logic naturally combine to make him a first-class lawyer. No surprise then that the 51-year-old litigation specialist gained a first in English from Jesus College, Cambridge, a PhD on T.S. Eliot and anti-Semitism, and the acknowledgement of his former client Stephen Fry as “the cleverest man I’ve ever met”.

Mr Justice Gray’s judgment in favour of Lipstadt was, according to Julius, “as close to a foregone conclusion as any in my experience”. Labelling this his most important case, he is proud “to have successfully defended Jewish interests and Jewish history against attacks by anti-Semites”. As an Orthodox Jew, it’s a cause very close to his heart: he is writing a 350,000-word history of English anti-Semitism for Oxford University Press, to be published next year. He is not, however, in favour of criminalising Holocaust denial — to avoid creating martyrs and because of freedom of expression. “The real threat to the Jews”, he suggests, comes not from the scattered tentacles of the far Right, but from political hostility to Israel.

One prominent Israeli who has recently retained Julius is Avram Grant. With two seasons to run on his £3.5 million-a-year contract, Chelsea have offered only 12 months’ compensation. Unhappy with these severance terms, and believing it contrasts unfavourably with the £12 million José Mourinho that received after his dismissal, Grant wants Julius to secure him a better deal.

Julius and I spoke before he was instructed by Grant. Although accustomed to being in the spotlight via prominent clients, he shuns the celebrity lawyer tag: “You’re on a higher wire and being stared at by a larger number of people,” he says. “But in the end, the only audience that matters is your own client.”

Former clients include Diana, Princess of Wales, on whose behalf he successfully negotiated a reported £17 million divorce settlement: the wire does not get much higher nor the spotlight any brighter. Julius was “extremely fond” of the late Princess — they lunched every month up to her death in August 1997 — and is “very proud” to be vice-president of the Diana, Princess of Wales Memorial Fund, the charity he established.

While turning down many cases, Julius often chooses work where “the people are most interesting”. Until last November he represented Heather Mills in her divorce from Sir Paul McCartney. After her emotional outburst on the GMTV programme This Morning, client and solicitor parted company. In March, after agreeing a £24.3 million divorce settlement, Mills said that the split had been “planned for months” and that she remained “very good friends” with Julius, whom she “respects very much”.

“My firm has an informed, intelligent gregariousness,” says Julius. Banking and finance apart, he suggests that lawyers in the “magic circle” firms are doing the same work as Mishcon de Reya: “They use the term ‘magic circle’ to create a cult aura, which is misplaced.” The competition, he believes, is between lawyers of the greatest competence and imagination. So how does he define his own skills? There is a long pause. “It’s so hard, I’m actually stumped,” he says. “Talking about oneself is one’s blind spot. I suppose I combine academic and forensic skills — it may be that’s a combination that works particularly well here.”

Last October, Julius’s second wife Dina Rabinovitch died of breast cancer, a condition she had movingly chronicled in her writing for The Guardian. She was 45. Julius now spends most weekdays from 5 to 8pm with Elon, their six-year-old son. He works until late thereafter. Very few busy lawyers manage their time so admirably. Family life is important: Julius is also father to four children by his first marriage and stepfather to Dina’s three children.

If success brings jealousy, Julius is no exception. Hence the epithet “Anthony Genius” — a sarcastic reference among competitors to his skills as a polymath. In 1995 he faced a critical onslaught when his book about T. S. Eliot’s anti-Semitism was published. “I can’t imagine that his current notoriety is giving Julius much satisfaction or pleasure,” wrote Will Self at the time.

To some degree, he clearly enjoys controversy. His next big project is a book on the trials of Lady Chatterley’s Lover and how the arguments about censorship and pornography have developed into a debate about censorship of blasphemy and speech which is considered disrespectful of religion. Mary Whitehouse, he suggests, was “a suffocating, sanctimonious bigot”. Outside the law and writing, Julius supervises a PhD student at Birkbeck College. “I’m doing everything I want to do,” he says, “and nothing I don’t want to do.”

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