Female spies using sex to obtain secrets may be a staple of espionage thrillers, but it has emerged that in reality British intelligence did not approve.

MI5 also instructed its staff on how to stop their female spies falling in love with targets, files newly-released to the National Archives show.  The advice was issued at the end of World War II by top MI5 agent-runner Maxwell Knight, the inspiration for James Bond spy chief "M". During the war, he headed the MI5 department recruiting agents to penetrate Nazi spy rings in Britain. Loss of interest: Like his fictional counterpart, he felt sex had no place in the serious business of espionage. "I am no believer in what might be described as Mata Hari methods," he wrote, referring to the World War I spy known for her many lovers.

Photos: Mata Hari in stage costume at Guimet Museum in Paris, 1905

"I am convinced that more information has been obtained by women agents by keeping out of the arms of the man, than was ever obtained by sinking too willingly into them. "If a man is physically but casually interested in a woman, he will very speedily lose interest in her once his immediate object is attained." Whereas if he can come to rely upon the woman more for her qualities of companionship and sympathy, than merely those of physical satisfaction, the enterprise will last longer." 'Ill-founded prejudice': Mr Knight felt the best way to ensure women agents did not fall in love with men they were spying on, was simply to steer them clear of their "type". When the officer is really getting acquainted with his agent, he should, in the case of a woman, pay particular attention to the types of men that the woman concerned likes and dislikes. "His future direction of her should, to a very large extent, be guided by the knowledge which he has obtained during this initial period." Knight did support the use of women agents though, dismissing a "very long-standing and ill-founded prejudice" against them. "A clever woman who can use her personal attractions wisely has in her armoury a very formidable weapon," he said.

Alexandra Kerry in Cannes.

Conservatives: "Do we really want a man who raised a daughter who dresses like this running the country?" Liberals: "Wow, Kerry's daughter went to Cannes - do you think she was at the Almodóvar party?". No comment is needed. Alexandra Kerry loomed out of the Cannes night like a Magritte nude, leaving the paparazzi pondering; "Did she dress in the dark? Was her postmodern take on visible panty line and Mister Magoo chic a ghastly accident — like an errant trail of loo paper — or a cunning ploy to lure lenses?" Whatever, it worked. More snaps were snapped of the frock-challenged US film director, and daughter of presidential candidate John Kerry, in her see-through mono-shoulder side-slit caped chiffon camera catcher, than of any other semi-famous-type-person at the 57th Cannes Film Festival this week.

WHAT'S HAPPENING OUT THERE?

Fashion is a dog's breakfast, and don’t we know it. For madam et monsieur, le menu du jour: Cardigans (thin and cashmere), florals (a tsunami of fresh flowery frocks and sundry separates is breaking, as we speak, over Britain and Europe and will build and break again over our coming spring/summer. Alannah Hill and Trelise Cooper mastered the art of floral arrangement early, in crisp combos with a nostalgic lilt), lioness curls (teased out to a voluminous tangle and best worn with something stringy for counterbalance), smoothed bobs (gathering momentum), puff sleeves (preferably sheer), metal-capped stiletto pumps (Helmut Lang's tripped off a trail of knock-offs requiring removal at airport metal-detecting security checkpoints), twisted T-shirts, crocheted lace mini frocks and skirts, fuchsia pink with gold, patterned tights, over-the-knee patterned socks, over-the-knee plain socks, lace socks (ankle, knee, mid-thigh), Corleone (jeans), playsuits (matched top and shorts, as interpreted by Alannah Hill for spring/summer 2004-05, pictured), patterned cotton bras (tripling as top, bra, and bikini), polka dots, floppy felt hats (in, out, in, out, in . . .), gingham, feather boas, fur stoles and capelets (summer or winter; if there's a nip, there's a need), faux lower lashes (of eyes, not whips), Prada Intimates (the knickers, quite lovely), cotton-knit shorts, fringing, lame and lurex, satin and lace.

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