A popular Cape Cod resort community is reliving a divisive nightmare of more than 50 years ago, when a serial killer named Tony Costa stalked the seaside paradise.
Provincetown, Mass., celebrated for its beautiful ocean scenery and soaring sand dunes, is also apparently confronting cancel culture.
The serial killer controversy exploded on social media this summer after an "angry online mob" silenced a pair of scheduled author events to take place at a local bookstore related to Costa's heinous crimes.
The mob in this case was not the family and friends of the victims — but allegedly the family and friends of the Cape Cod killer himself.
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Antone Charles Costa was convicted in 1969 of the dismemberment murder of two women; he was suspected of killing six others. He hung himself in prison in 1974.
He’s the subject of two new books: "The Babysitter: My Summers with a Serial Killer" by Liza Rodman and Jennifer Jordan, published in 2021; and "Helltown: The Untold Story of a Serial Killer on Cape Cod" by Casey Sherman, released this July.
Costa "was the most vicious serial killer in American history," Sherman told Fox News Digital in an interview.
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He described how the 24-year-old carpenter stabbed, shot, dismembered and removed the organs of his victims.
Author Kurt Vonnegut even likened Costa to Jack the Ripper in a 1969 Life magazine story.
"We were bullied by an angry online mob." — Author Liza Rodman
"The Babysitter" author Liza Rodman was scheduled to appear at East End Books on June 28 to discuss her relationship with Costa, who actually babysat her when she was a child in the 1960s.
But when a social media outcry arose, she canceled the event, fearing violence.
She also said she received threats via email in 2019 while she was researching the book.
"Disgusting!!! Shame on you!!!" charged one person on a community Facebook page.
"East End Books should be absolutely ashamed of themselves, just as bad as the author IMHO," posted another.
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The bookstore itself preemptively canceled a scheduled August 6 appearance by Sherman amid the online outbursts.
"I'm a bookseller. We want to promote the exchange of ideas," East End Books owner Jeff Peters told Fox News Digital by phone.
"I felt blindsided by what looks like a vigorous, coordinated attack by a small minority of people."
The tenor of the attacks grew nastier in the days and hours before the scheduled June 28 event with Rodman, who reported the threats to local police.
"By the way, I also am trained in hand-to-hand combat," reads an email, in part, that Sherman received on June 24 and that he shared with Fox News Digital.
"There are many, many folks out there who would be glad to get a good crack at your chin."
Fox News Digital reached out to the email sender for comment.
"We were bullied by an angry online mob," said Rodman, expressing her beliefs.
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"These self-named ‘townies’ are friends and family members of Tony Costa, a serial murderer, not the families of his victims," Rodman writes on her personal blog.
"In a bit of deja vu, they once again closed ranks posting hundreds of comments designed to intimidate and defame."
Provincetown, a scenic community at the tip of Cape Cod — noted in history as the spot where the Pilgrims first set foot on the New World — touts itself in online marketing as a haven of "individuality and freedom of expression."
"Free speech. People in town have talked openly about this for year," wrote Mark S. Morgan, in support of the authors, on Facebook.
"If you are ‘triggered’ by [the book] don’t read it. Or shall we have a book burning?"
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"This is definitely censorship," said Rodman to Fox News Digital.
"It’s the climate we live in. The shutting down of people by an angry mob. Suddenly this kind of stuff works."
Fox News Digital reached out to Provincetown's town manager and others connected to this story for comment.