[In the following excerpt, Williams deems White Butterfly an "altogether harsher, more serious piece of work" than its predecessors.]

White Butterfly is the third novel by Walter Mosley, the man now doomed to be referred to continually as "Bill Clinton's favourite writer". This is an altogether harsher, more serious piece of work. Mosley's novels are intended to form a cycle, providing a massive portrait of life in black Los Angeles over the postwar period as experienced by the reluctant PI Easy Rawlins.

White Butterfly sees the action move to 1957. A serial killer (yes, yet another one) is preying on black prostitutes in south central LA. No one cares much until a white hooker dies, a rich girl gone bad. Then all hell breaks loose and Easy's called in. Naturally, he solves the case.

As plots go, White Butterfly's is functional and little more. But then Mosley's plots are Trojan horses. They let him into the airport bookstalls, they even let him into the White House, and they allow him to tell something like the truth about black life in the US ghetto. In particular, in this case, to say something hard and sad about the relations between black men and women in a society governed by racism.