Complex sentence: Realizing he was set up, Gittes figures whoever did it wants to get Mulwray, but, before he can question him, Lieutenant Lou Escobar (Lopez) fishes Mulwray, drowned, from a fresh water reservoir.
Split into simpler sentences: Realizing he was set up, Gittes figures whomever did it wants to get Mulwray. Before he can question the Mr. Mulwray, Lieutenant Lou Escobar (Lopez) fishes Mulwray's body from a fresh water reservoir.