Search - Two Graves (Pendergast, Bk 12)

I hate to say it, as much as I like Preston and Child, but Two Graves was almost too painful to read, and made a most disappointing end for the Pendergast and Helen story arc. The books in this series all have a touch (or more) of the macabre and the fantastic, but really? Evil twins and Nazis is the best they could do? The plot is heavy on action and hardware but short on heart. Pendergast himself is almost an automaton, driven beyond reason to pursue whatever it is he's pursuing--revenge? justice? I'm not sure, and he doesn't seem to be, either. Even after this I'm not quite ready to abandon a series I've enjoyed so much, but it's definitely losing its luster.