Not up or disinterest context?

To finish the trilogy, James Ellroy book so we Underworld USA after American Tabloid and The Cold Six Thousand. The period is 1968 (Robert Kennedy and Martin Luther King died) to 1972 (J. Edgar Hoover died).

Both the first two parts had literally bewitched me punchy writing, addictive characters (Kemper Boyd, Litell Ward, Pete Bondurant), numerous interest collusion, as this last component was surprised by the lack of size of main characters, even their transparency ... In addition, the period may be, in my opinion, less exciting.

Result, this final book is tasteless, I even struggled to finish, feeling that James Ellroy did not know how to finish it ... I reread the first two parts but not the third ...