While a bit atypical (most sociopaths are male), this episode is nonetheless an excellent study into violent sociopathy. It also drives home the fact that sociopaths can come from all walks of life, and that an increasing number of violent sociopaths are female.
The fact that SVU detectives Olivia Benson and Elliot Stabler are brought in was the first clue to me that this was not going to be your typical L&O story, and so it wasn't. Then, the chilling scene where the victim's sister casually asks about her jewelry in the throes of the investigation into her sister's brutal murder is what took this to a "10" for me.
Call "Fools for Love" 'Silence of the Lambs' L&O style.