It’s been an astonishing musical career for American folk-jazz artist Terry Callier – if his course could be called a career in the commercial sense. In recent years, the 57-year-old Callier’s career has been revived after critically acclaimed work from the mid-1960s right through to the artist’s eventual detachment from music 15 years later, yet it had gone by virtually unnoticed. Callier ceased performing to his limited cult in the early 1980s, but a surge of interest in his work a decade later brought the artist out of musical retirement. He had been working as a computer programmer while writing and releasing new material on the side. But these days the artist, whose deeply spiritual music defies simple categorization, is a frequent stage performer by popular demand. Currently on tour in Europe, Callier will perform one show at Club 22 (22 Vouliagmenis, tel 210.924.9814) on Sunday. The comeback was prompted by a surprise phone call in 1991 from fan Eddie Pillar, the head of UK label Acid Jazz, who sought permission to rerelease Callier’s little-known 1983 single «I Don’t Want To See Myself (Without You).» It became a massive hit on the British club circuit. Shows have since followed on both sides of the Atlantic, while more well-received work has been released. Callier has also collaborated on record with the far younger English neo-folk singer Beth Orton, a self-sworn fan.