Strangulation, beheading, mutilation, equine arson, adultery, addiction, redemption.

Sopranos fans said Sunday's blood-drenched episode, in which mobster Ralphie Cifaretto had his head and hands chopped off and dumped in a bowling-ball bag, was one of the most shocking ever -- and true to the Mafia's actual murder methods.

So whose head will roll next? A poll of Sopranos addicts fingers Paulie "Walnuts" Gaultieri, who was talking out of school when he was jailed on a gun rap in Ohio.

Another candidate is Johnny "Sack" Sacramoni, the New York underboss to whom Paulie divulged a Soprano family secret: Ralphie's "fat" jokes about his wife Ginny.

Allen Rucker, author of The Sopranos: A Family History and a friend of creator David Chase, said the details of Ralphie's murder were based on gruesome accounts of mob methodology.

"This was the real deal," Rucker said. "It all happened. The Murder Machine was a Brooklyn crew that killed hundreds of people in a place called 'The Horror Hotel.'"

He said Sunday's episode mirrored actual events in which the Brooklyn mob had drained their victims' corpses in a bathtub.

"They hacked them up, then sent them out in dump trucks," he said. "They killed hundreds of people," said Rucker.

The author said he thought the Sopranos killing was not premeditated.

"Tony didn't know he was going to kill Ralphie when he walked in there," he said. "There was no intention. We sometimes don't know what we're going to do or say. One act of violence precipitates another. It was natural to the story."

On the Sopranoland.com Web site, fans speculated capo Ralphie's murder may have been retribution for his sexual eccentricities.

"It was heavenly payback," said a message poster called "Carlito."

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