Metro

Billy Joel hires Paul McCartney’s detective to foil daughter’s stalker

A cyberstalker barraged Billy Joel’s daughter with Facebook messages that were so terrifying that the Piano Man hired pal Paul McCartney’s best private eye to hunt the creep down.

Sheryl Finley, 40, was found naked in the frigid woods of Minnesota and charged with stalking 27-year-old Alexa Ray Joel for several months.

Finley wrote more than 60 messages via Facebook, with some involving “pedophilia, sadistic-sexual behavior, violent physical assaults and murder,” court records allege.

The horrified songwriter was afraid to leave her Manhattan home, sources said.

“Her mother, Christie Brinkley, was terrified that someone would harm her baby,” a source told The Post. “Billy Joel was worried but focused.”

The singer hired a bodyguard to protect his daughter and contacted McCartney, who recommended a Europe-based private-security firm not bound by the same legal restrictions as the police, the sources said.

McCartney’s people found the stalker in Austin, Minn.

She weirdly told law enforcement that the rape and murder she allegedly threatened in the messages were not things she wanted to do “during this life,” according to court records.

Finley, who spent a few months in a mental institution in 2010, remained hopeful that Alexa Ray would not “object to meeting with her.”

A representative for Alexa Ray and Billy Joel declined to comment. McCartney’s publicist did not reply to requests for comment.