'Brutal and barbaric': Marshfield writer tells true story of Cape Cod killer in 'Helltown'

MARSHFIELD – Casey Sherman has written about murderers before, ones whose names and deeds are instantly recognizable.

The Boston Strangler. The Boston Marathon Bombers. Whitey Bulger.

In his 15th book, "Helltown," on sale from sourcebooks, Sherman writes about a killer on his native Cape Cod, one who has been largely forgotten over the past half-century and lives on through a nickname, "Tony Chop-Chop."

Antone "Tony" Costa was a sometime carpenter and a handyman, drug dealer and police informer. On a late January weekend in 1969, Costa met up with two young women from Providence, Patricia Walsh and Mary Anne Wysocki, who chose the rooming house where he lived for a weekend getaway. Costa persuaded the young women to give him a ride to pick up his paycheck. Afterward, he took them to a wooded area of North Truro, where he killed them both, dismembered them, and buried them in shallow graves.

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"To me, it was the worst serial murder case since Jack the Ripper, who stalked the streets of London's East End a century earlier," Sherman said. "I was shocked the case was lost to history. The story was really forgotten. And, more importantly, these young women were forgotten."

Sherman used police files and trial transcripts and interviews with surviving investigators to document the case against Costa, who was convicted of the murders and is suspected of three others. He also draws on Costa's unpublished memoir titled "Resurrection."

He won't say how he got  the manuscript.

"It turned everything on its head," Sherman said of the manuscript. "I could bring the reader to the crime scene through the eyes of the killer."

He said Costa had ambitions of being a writer.

The case also attracted the interest of two literary heavyweights living on the Cape at the time: Norman Mailer, who had a house in Provincetown, and Kurt Vonnegut, a struggling car dealer whose  career as a writer took off with the publication of "Slaughterhouse-Five." One of Vonnegut's daughters had met Costa.

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"This was a case that haunted Norman Mailer and Kurt Vonnegut," Sherman said.

Vonnegut wrote about the case for "Life" magazine and attended the trial. While he wasn't in the courtroom, Mailer kept a close eye on developments and incorporated elements of the story into his novel and movie "Tough Guys Don't Dance."

While the Cape Cod murders were initially national news, they were eclipsed a few months later by the Tate-LaBianca murders in California by Charles Manson and his followers.

A New York Times bestselling author, Sherman, 53, of Marshfield, got the idea for the book when he went for a drive through Provincetown with his brother, Todd, during the coronavirus lockdown, passing by sites that figure into the story. He started his research as soon as he got home.

"I didn't want to glorify Tony Costa," who was 29 when he killed himself in prison in 1974. "I wanted to explain the monster in the most realistic way possible. Costa was brutal and barbaric and he was alive and living on Cape Cod."

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"He was cocky, charming and thought he was smarter than the cops. He tried to stay one step ahead of the detectives, but the detectives were ultimately smarter," Sherman said during an interview at Station 8 in Marshfield Center.

The detectives found the bodies, as well as key pieces of evidence, without the high-tech equipment familiar to readers of more recent true-crime cases.

Sherman also wanted to write about the period, from the election of Richard Nixon, the Chappaquiddick incident, the protests over the Vietnam War and the moon landing as well as the "hippie" community that Costa was a part of.

He is working with actor Robert Downey Jr.'s production company to develop "Helltown" into a limited-run television series.

He has also started work on a book about Lana Turner and Johnny Stompanato. He was killed in 1958 in Turner's home, allegedly by her daughter during a domestic dispute. It's a story that brings together "gangsters and Hollywood glamour," Sherman said.

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There are others with his friend and frequent collaborator Dave Wedge, of Milton, including a third season of their "Saints, Sinners and Serial Killers" podcast and fine-tuning the live version of the show that was first produced in April at The Wilbur in Boston and taking it back out before a live audience. And they are looking at another book project, which would be their sixth together.

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Excerpt from 'Helltown'

"(Massachusetts State Police Detectives) Tom Gunnery and Bernie Flynn then led the shackled suspect off the elevator onto the first floor as the sound of flashbulbs crackled through the lobby. Bernie Flynn stopped to address reporters.

"Antone Costa is a suspect in a double murder involving two girls missing from Providence, Rhode Island since January 25," he said. "We have no more information at this time."

The killer made no attempt to cover his face. He seemed to enjoy the attention.

Costa's cuffed hands were attached to a restraining belt tied to his waist. He moved slowly toward the front door of the barracks, trying to take the moment in. Gunnery squeezed his triceps and ushered him out the door to the parking area where a convoy of police vehicles waited with their lights flashing. The killer smiled as he was placed in the back seat of the second cruiser.

"This is quite the spectacle," Costa said aloud. "I wonder what reception I'll get when I return to Cape Cod."

Meet Casey Sherman in Hingham

Sherman will discuss "Helltown" at 7 p.m. Wednesday, July 27, in the Whiton Room of the Hingham Public Library, 66 Leavitt St.  Reservations can be made for the free program on the library's website, hinghamlibrary.org.

This article originally appeared on The Patriot Ledger: The true story of a Cape Cod killer in 'Helltown' by Marshfield author