Kimberly McCullough, Jason Thompson Kimberly McCullough, Jason Thompson

Spoiler Alert! One of the best General Hospital villains ever is about to die  by monkey wrench! The ABC soap kicks off an epic whodunit this week that finds several Port Charles favorites (Patrick, Robin, Matt, Maxie, Elizabeth, Olivia, Steve) celebrating on a rented party boat unaware that the psychotic Dr. Lisa Niles (Brianna Brown), whom everyone thinks is in a coma, is hiding among them in plain sight.

"Lisa is out to destroy Patrick and Robin and decides this would be a good time to make her move but, truth be told, she doesn't like anybody on board," exec producer Jill Farren Phelps tells TV Guide Magazine. "This is Lisa's worst, most insidious plan yet." And it ends very badly for her. Lisa's death — apparently by blunt-force trauma — will leave every one of the passengers looking guilty. "Each of them ends up having the motive, the means and the opportunity to kill her," Phelps says. "It's a very cleverly told mystery."

And it will play out for months. Phelps says viewers won't learn the identity of the killer until February. In the meantime, she notes, "this will become a story about how far people will go to protect the one they love. Couples will be suspecting each other. We'll introduce a new mystery character. And someone gets a very serious disease as a result of what's happened."

Blame it all on mob king Anthony Zacchara, who gave Lisa the drugs that bring her back to consciousness. "He has unleashed the she-devil from hell for his own nefarious reasons and he will play a very delicious part in the fallout," hints Phelps. "Lisa really gets him good!"

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