Love in a time of war. And with Simon Keenlyside and Malcolm Martineau to meditate upon it, it is small wonder that there wasn't a seat to be had. What is more, Keenlyside was beginning the Wigmore's series of eight concerts, devised by Martineau, in which Poulenc's entire song output will be covered for the first time in a single season in London.

Poulenc is at his most moving in adversity; and songs written during the Occupation, such as Le disparu, fuse musical nonchalance and pain in a way in which Keenlyside's baritone knows just how to respond. The melancholy of Mazurka, and the mordent sensuality of Un poème, found answering colours in his sensitised palette of a baritone.

Both Keenlyside and Martineau really came into their own in the elusive aching of pain and pleasure that hangs over Poulenc's settings of the surreal poetry of Paul Eluard in the nine songs of Tel jour, telle nuit. Keenlyside's searingly powerful head voice, and his sensing out of the nerves and sinews of the French language, was thrilling, and moving too.

None of these songs would have had quite such a powerful effect had they not immediately followed a quite outstanding performance of Butterworth's A Shropshire Lad. It's not the sort of thing you'd expect Keenlyside to take on, perhaps; yet this was possibly the most eloquent performance that this hall has heard in decades. The opening word of Loveliest of trees, poised high and hushed, carried the scent and the bloom of spring in the voice. And Keenlyside's fusion of earthy, conversational inflection with classical poise exactly recreated the sensibility of Housman's poetry.

Keenlyside had begun with Schumann's Dichterliebe. He sang more freely once it was over, as though aware that, for him, this was the supreme Wigmore Hall test piece. But his deceptively artless approach (it recalled Keats's words about the need for poetry to come as naturally as leaves to a tree) won the audience over, and Martineau's playing supplied any remaining subtext of wonder or angst.

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