As we were in the throes of dissecting the Democratic debate last night, word crossed that the death of Drew Peterson's third wife had just been ruled a homicide. In case you need a refresher, he is the ex-cop named a person of interest in the disappearance of his fourth wife, Stacy Peterson. She went missing in late October. Her family says the young mom would never leave her children; Drew Peterson claims his wife left him for another man.

He's an interesting character. Drew Peterson instantly seemed to love the media spotlight when his fourth wife disappeared, while at the same time complaining about the attention. Since his fourth wife went missing, Peterson has hired a publicist, said he's ready to start dating again, and offered up letters and anonymous tips from people claiming to have seen Stacy Peterson.

Now the focus is back on the death of his third wife, Kathleen Savio. Her death was ruled an accidental drowning in 2004. She was found in a dry bathtub. When Stacy Peterson went missing, the investigation into her death was reopened; her body was exhumed; a second autopsy performed. Now, we are told her death was actually a homicide. Drew Peterson expressed surprise at the news. Authorities have not identified a suspect.
 
What makes this guy tick? Why the strange details surrounding his wives? We're digging deeper on that tonight on 360. Let us know what you think. And please join us.

-Erica Hill, 360° Correspondent