The Lennon heads; centrepiece

Here's one strictly for the die-hard fans: an exhibition and limited- edition book of photographs of John Lennon and Yoko Ono taken in New York over the last two decades of Lennon's life. "Bob Gruen was there at all the important moments," Yoko Ono says. And so he seems to have been - take the pictures of Lennon with his baby son Sean, sitting cross-legged on his bed, looking downright silly in a kimono and ponytail. Nothing unusual about that, you might say. But more unusual is the foolishly happy grin on his face - enough to make you look twice. How many pictures are there of Lennon, in his thirties, looking relaxed and at ease with himself? The face on the cover of his last album, Double Fantasy (in profile, standing outside the Dakota building), is unsettlingly mask-like, an image that belies the celebratory tone of what was, after all, a much-heralded comeback record.

But while New York-based photographer Bob Gruen's rock'n'roll collection includes stars like Mick Jagger, the Clash, Chuck Berry and Patti Smith (also on show here), his portraits of the Lennons are the most compelling. For fascinating evidence of a famously complex relationship, witness a picture of the Lennons in a rowing boat in 1973 (right) - John playing the fool for the camera while Ono looks on with the intensity of a lioness watching her young.

But for those with doubts about the strength of Lennon and Ono's relationship, look no further than the 1972 shot of the Lennons literally wrapped up in each other - John playing guitar while Ono dances along to the music, her arms draped around his neck - every bit a part of his work. If every picture tells a story, this was, as Ono puts it, "the big one".

Jane Richards

`Bob Gruen: Sometime in New York City', The Special Photographer's Company, 21 Kensington Park Road, W11 (0171-221 3489) to 20 May. Signed, limited-edition book £275