Passion concentrates on Grainger's unusual relationship with his mother and his sexual peculiarities (especially his obsessive self-flagellation, though homosexuality is also hinted at) which affect his relationship with a woman who comes to love him. It is set mainly in London in 1914, when Grainger's mother Rose was ill (she would later jump to her death in New York, upset by ill-founded rumours of incest with her son).

"Between music and love lies a secret obsession."