The first half is semi-interesting and psychological, the second half is the most dull and formulaic murder 'mystery'. Fetishizes women and seemingly normalizes sexual violence in only that way 20th century 'hard boiled' detective novels can. The reason the main character of the first half turned crazy in the first place? 'Uhm, female emancipation and progressive social pressures actually.' Reaaaal good social commentary there, truly ahead of the time.
If you're planning on giving this a try, do yourself a favour and stop after part 1, or rather don't start at all.