THINK Alan Bennett and you're more likely to think DSS than KGB. The characters that inhabit Bennett's world are benefit-claiming northern troupers with no greater aspirations than towards acquiring a touch of middle class respectability.

But England's Queen Mum of playwrights periodically shows there's more to his repertoire than bitter-sweet slices of Yorkshire life.

His critically acclaimed Cold War-themed Single Spies is a double-header at Guildford's Yvonne Arnaud Theatre until tomorrow (Saturday).

Taking his inspiration from the unlikely source of double agents Guy Burgess and Anthony Blunt, the settings of Burgess's squalid Moscow flat, and some years after his retirement from espionage, Blunt's domain at Buckingham Palace as the Queen's art surveyor, are a million miles from the terrace houses of Bennettland.

But he seamlessly mixes the rarefied with the prosaic with some characteristically deadpan one-liners.

In An Englishman Abroad, Australian actress Coral Browne (Liza Goddard), touring Moscow in Hamlet, recalls her first meeting with the exiled traitor Guy Burgess (Robert Powell). (Burgess threw up in Michael Redgrave's dressing room).

"Vomiting isn't like childbirth. You can complete the task unaided," recalls Browne, excellently played as little more than a trollop in a fur coat by Goddard. The only slight mystery being her cracked bell of a cockney accent - odd considering she was from Melbourne.

Visiting the dissolute Burgess in his pigsty of a flat, she ends up running errands for his Savile Row suits, which, for the long exiled traitor, act as one of his few reminders of England.

Powell as Burgess, with his rounded vowels, crumpled Eton necktie and tendency towards self-absorption, is every inch an establishment figure, albeit one who tried to bring down his very sort by spying for the Russians.

For the second play, A Question of Attribution, Powell almost reprises his performance in the first to play the similarly self-regarding, if more uptight Anthony Blunt.

Like Burgess, Blunt spied for the Russians, and aside from a Cambridge University and espionage background, they shared a love for each other, which is hinted at but never fully explored.

In Bennett's play, Blunt's spying days are behind him, but even in his new lofty position as the Queen's art surveyor, there is no escaping the suspicion that he was "the fourth man" in the Cambridge Spy Affair.

One of Blunt's students at the Courtauld's Institute, an incongruously middle-aged suburbanite (a detective played by Timothy Kightley), is decidedly dogged in his questioning about the authenticity of the paintings he is studying. Deception in the art world is not the only sort of deception he is interested in though.

For a man with a secret there is no hiding place for Blunt, even Her Majesty herself (played by Goddard) seems enigmatic in her ostensibly innocent questions about the meaning of art. Only a lofty few would be able to vouch for the convincingness of Goddard's portrayal as our head of state, but her resolutely imperious face belies a latent sense of mischief which seems to ring true.

Though erudite and witty, Single Spies is all the less engaging for having no plot and no sense of purpose. The two plays give a window on a little-known world, but despite some leavening humour, the two central characters' pomposity and love of the sound of their own voices makes one feel like a browbeaten student in one of Blunt's art classes. James Bowman