Three years ago Jason Rebello, rising star of the new Brit Jazz scene, quit playing to become a Buddhist monk. Now he's back.

Phil Johnson meets the man behind the press release.

It's such a good story, it seems a shame to let mere facts get in the way. A brilliant and handsome young pianist at the top of his career suddenly packs it all in to go off to a Buddhist monastery in search of the meaning of life. After experiencing the stern discipline of monastic routine, he slowly finds himself once again and realises that his true gift is to make people happy through his music. He therefore bids a sad farewell to his fellow monks and leaves the monastery to play a fabulous comeback concert at the Royal Festival Hall, where amid the cheers and the ovations he meets his old flame backstage. They embrace passionately before he nips out front again for an encore, probably a bit of Rachmaninov. The pianist could be played by Brad Pitt, the monastery could be in Tibet, and Helena Bonham Carter could supply the love interest.

Well, it's nearly true. Jason Rebello is the pianist, and he is young, brilliant and handsome. He is also playing the South Bank tonight, although it's really the tiny Purcell Room and not the larger RFH (but this is British jazz, right?).

The performance is something of a comeback, too, even if it's not in fact the first time he's stroked the ivories in public since he quit the cloister. And the monastery? Yep, there is one, but it's in Bradford-on- Avon, just outside Bath, rather than atop the Himalayas. Jason hasn't exactly left it either, although he's no longer a full-time monk. In fact he was only there for a couple of months, two years ago, but he still lives within sight of the place and goes there regularly to meditate. And finally - sorry, Brad - the Buddhism wasn't an overnight conversion; Rebello had been easing himself into it for years.

"I'm probably not cut out for a meditative life," Rebello says, a little embarrassed at the rather enthusiastic spin the promoter of tonight's concert has put on the Buddhist angle. "It's a tough thing to do, to become a monk. Being really honest, leaving the monastery came down to my reluctance to give up my own way of life. I was just too frightened to do that, and I didn't have the necessary detachment. You get up at 5.45am and do five hours of meditation a day, as well as lots of work, and coming from the lifestyle I was leading, it was the complete opposite. I intended to go for a few years but in the end it was only a few months because it became too difficult."

Rebello's story contains the seeds of yet another potent myth, in which his retreat (such as it was) can be seen as a response to the waning of the brief British jazz revival of the late Eighties and early Nineties, of which he was first a beneficiary and then a casualty. Following the success of Courtney Pine and Andy Sheppard for Island Records, Rebello was signed to BMG's Novus label in 1989; his debut album, A Clearer View, was produced by the star American saxophonist Wayne Shorter. Two further albums followed before his contract, like those of Pine and Sheppard, was dissolved when sales did not meet expectations. But this version of events is probably no nearer the truth than the first. Just before his decision to retire, Rebello had achieved his greatest fame so far, when he appeared as a TV presenter for BBC2's pop-culture series Artrageous, a role he looked quite comfortable with.

Still only 28 years old, Rebello thinks that it may have been his precociously early success, as much as anything else, that led to his gradual disillusionment with music.

"I was trying to find a new meaning because I was getting increasingly dissatisfied with the way things were going," he says. "Sometimes, when your dreams are fulfilled early, you feel, `Is that all there is?' You work hard and get success, which is what you hoped for, but your idea of what it will be like is much more pleasant than it actually is, and as a consequence you feel let down. You think, `Yes, if I'm successful, I'll be really happy and secure', but it doesn't really work like that."

The interest in Buddhism had been growing steadily ever since his professional career took off after he left the Guildhall School of Music in London in 1986. "I think what attracted me is that it's very logical - Buddhism can appeal to Westerners because they have this logical bent. You're not asked to believe things blindly; you're testing them out, almost like you're a scientist - you're trying to find out what is real."

For a jazz musician, the attraction of a philosophy that prizes the perfect moment above all else is very powerful, and many instrumentalists have compared the act of improvising to a kind of enlightened state. Sonny Rollins has talked about how he knows he is playing at his best if, in the midst of a solo, he loses himself in the music to the point where the saxophone seems to be playing him rather than the other way round. "In a sense, it's the self that impedes everything you do," Rebello says. "You're constantly trying to give up the idea that you're calling the shots. When you're playing, the idea of self is what makes it go wrong. When there's no me, there's no problem!"

Rebello's own style as a pianist doesn't, at least on the surface, suggest the intervention of any mystical force - unlike, say, the keyboard meditations of Keith Jarrett, a Gurdjieff man, or Bheki Mseleku, who used to accompany Krishna devotees at a shrine in Balham. By contrast, Rebello is one of the most worldly-sounding of players, elegant and epigrammatic in the manner of Errol Garner or the great Art Tatum, and with an ear alert to the rhythms of funk and soul.

Rebello's pursuit of the perfect moment of improvisation is also being paralleled by a renewed interest in composition, and what could be the beginnings of a classical career. On Friday, a concert in the Park Lane Group's annual "Young Artists New Year Series" (also, as it happens, at the SBC's Purcell Room) features an arrangement Rebello has made for two pianos. "The piece is written so that it should sound like two jazz pianists improvising, almost like taping them and then writing it out," he says. Tonight's jazz concert features both a solo set, and a trio with bassist Wayne Batchelor and drummer Darren Beckett, but Rebello denies the press release's assertion that he will be playing Jazz Meditation, described as "a piece he wrote in his head when meditating in the monastery". "No," he laughs. "I'm just playing some tunes." It looks as if Rachmaninov, Brad Pitt and Tibet will have to wait a little longer.

8pm tonight, Purcell Room, SBC, London SE1 (0171-960 4242)