MI6: Life and Death in the British Secret Service, By Gordon Corera

The move of MI6 in the late Nineties from modest, relatively covert premises (though bus conductors were prone to yell, "Spies alight here") to one of the most glossily ostentatious buildings in London was not welcomed by many of the staff, who referred to their new home as Legoland.

When the Bond movie The World is Not Enough was shown there, a scene depicting an explosion at Vauxhall Cross was loudly cheered. However, the conspicuous nature of the building is at least in keeping with the significance of MI6 as a major inspiration in British fiction.

This fast-moving account by the BBC's Security Correspondent reveals that the true story of Britain's overseas intelligence service is as gripping as any novel. Inevitably, Kim Philby plays a central role in the early stages.

Gordon Corera pursues this icy, plausible figure from pre-war Vienna, where his involvement with a local girl was later utilised in The Third Man by his friend Graham Greene, through his unhindered climb virtually to the top of MI6.

When an MP accused him of "dubious Third Man activities" in 1956, Philby coolly won round a press conference. After his defection in 1963, Greene expressed admiration - "I myself would not have been capable of such courage" - but John le Carré refused to meet him. "I couldn't possibly shake his hand. It was drenched in blood."

Corera works wonders in untangling the murky, convoluted doings of the organisation through the decades. Probing the murder of Congolese activist Patrice Lumumba in 1960, he states, "It is clear that those who ordered the killing were close to the CIA and MI6 in the Congo."

our decades on, he quotes an MI6 officer that "British intelligence facilitated the transfer" of Libyan opposition members to the jails of Colonel Gadaffi. Exploring the dud information supplied for the "dodgy dossier" on Iraq, he notes, "The impact on MI6's reputation was calamitous."

MI6 may remain a secret service of sorts, but is it only too evident why Corera concludes by stressing the need for "a credible system of accountability".