Ellroy finds his feet in this second volume of the Lloyd Hopkins trilogy.  Hopkins himself seems more real, and the lead woman character also seems to be given a bit more psychological leeway by Ellroy (she does remain a sex worker, though - roll your eyes at Ellroy now folks).  Most importantly, Hopkins' unknown enemy, a truly awful cult leader, is given both flaws and strengths, moves and counter-moves by Ellroy. You do think about half way through that there's a strong possibility that he will win, which is almost unheard of in a cop novel. Ultimately it's the mastery of character that makes this a fantastic read, not the somewhat generic depiction of L.A. in the eighties. Incredible jump in quality after the first novel.