The Monster of Florence: Zodiac Killer Theory & Suspects

The Monster of Florence: Breaking Down the Suspects and the Zodiac Killer Theory

Some true crime cases wrap up neatly with a conviction and a closed file. Others linger for a few years before a lucky DNA hit solves the puzzle. Then you have the cases that refuse to die — the ones that mutate, twist, and pull you down a rabbit hole so deep you forget which way is up. The Monster of Florence is the ultimate labyrinth.

Between 1968 and 1985, a phantom stalked the breathtaking hills surrounding Florence, Italy. He targeted young couples seeking privacy in their parked cars. He didn’t just kill them. He completely butchered them. Decades later, the Italian police have exhausted over 100,000 investigative hours. They have arrested local farmers, investigated wealthy satanic cults, and chased a gun that seemingly vanished into thin air.

Yet, the most terrifying theory of all points to an American. Could the monster who terrorized Tuscany be the exact same man who terrorized Northern California? Was the Monster of Florence actually the Zodiac Killer?

Key takeaways

• The Crimes: Between 1968 and 1985, a serial killer murdered 16 people (eight couples) parked in secluded lovers’ lanes around Florence, Italy.
• The Modus Operandi: The killer always used the exact same weapon — a .22 caliber Beretta pistol firing Winchester copper-clad bullets stamped with an “H” . Female victims were often horrifically mutilated.
• The “Snack Buddies”: Italian authorities eventually convicted a group of aging, violent farm laborers led by Pietro Pacciani, though physical evidence tying them to the scenes was practically nonexistent.
• The Zodiac Theory: A compelling journalistic investigation points to an Italian-American US Army CID investigator, Giuseppe Bevilacqua, who lived in California during the Zodiac murders and moved to Florence just before the Monster struck.
• Pop Culture Resurgence: The case is experiencing a massive revival. Following a hit 2025 release, Netflix began filming a new 2026 miniseries focused specifically on prime suspect Pietro Pacciani.

The Modus Operandi: Tuscan hills

The beautiful but isolated hills surrounding Florence became a hunting ground. Source: Getty Images

To understand the absolute panic this killer caused, you have to understand the setting. Florence in the 1970s and 80s was steeped in romance and Catholic tradition. Young people living with their strict parents had nowhere to go for physical intimacy. Their only option was to drive out into the rolling, cypress-lined hills at night, park down a dirt road, and steam up the windows.

The Monster weaponized that vulnerability.

He stalked these secluded spots on moonless nights. His attacks were lightning-fast and unbelievably savage. He always approached the passenger side of the vehicle, shooting through the glass to eliminate the male driver first. Then, he turned his weapon on the female passenger.

His firearm of choice was incredibly specific. Ballistics matched the exact same gun across all eight double murders: a .22 caliber Beretta pistol. The ammunition was just as distinct. The killer used Winchester copper-clad bullets, manufactured in Australia in the 1950s, each stamped with a prominent “H” on the casing.

Shooting the victims was never enough.

Once the couples were dead, the killer dragged the female victims out of the car. Using a heavy, razor-sharp blade — likely a diving knife or a scalpel — he surgically excised their pubic areas. In the later murders, he escalated his depravity by also removing the left breast. He took these gruesome trophies with him into the dark. He never left a fingerprint. He never left a footprint that could be definitively tracked.

Timeline of terror

Couples parked in small, vintage vehicles were the killer’s primary targets. Source: mrohana / Getty Images

The killer operated with a terrifying patience. Months or even years would pass between attacks, letting the public drop their guard just enough before he struck again.

1. August 21, 1968 (Signa):

Barbara Locci and her lover, Antonio Lo Bianco, were shot to death in an Alfa Romeo. Shockingly, Barbara’s six-year-old son, Natalino, was asleep in the backseat. The killer spared the boy. Natalino woke up, found the bodies, and wandered two kilometers in the dark to find help.

2. September 14, 1974 (Borgo San Lorenzo):

Pasquale Gentilcore (19) and Stefania Pettini (18) were parked in a Fiat 127. After shooting Pasquale, the killer dragged Stefania from the car and stabbed her 96 times. This marked the dramatic escalation of his post-mortem violence.

3. June 6, 1981 (Scandicci):

Giovanni Foggi (30) and Carmela De Nuccio (21) were murdered on a Saturday night. This was the first time the killer surgically removed the female victim’s pubic area.

4. October 22, 1981 (Calenzano):

Stefano Baldi (26) and Susanna Cambi (24) were parked near a dark field. The killer struck again, repeating the exact same horrifying mutilation on Susanna.

5. June 19, 1982 (Montespertoli):

Paolo Mainardi (22) and Antonella Migliorini (19) realized they were being attacked. Paolo actually managed to start the car and tried to drive away, but he crashed into a ditch. The killer walked up and executed them both. Police deliberately leaked false information to the press, claiming Paolo woke up in the hospital and named his attacker. The bait failed. The killer stayed perfectly quiet.

6. September 9, 1983 (Giogoli):

Two young German tourists, Jens-Uwe Rüsch (24) and Wilhelm Friedrich Meyer (24), were shot in their Volkswagen bus. Because Rüsch had long blonde hair, investigators strongly believe the killer fired in the dark, mistaking the two men for a heterosexual couple. Realizing his error, he performed no mutilations and quickly fled.

7. July 29, 1984 (Vicchio):

Claudio Stefanacci (21) and Pia Rontini (18) were murdered. The killer escalated his violence again, removing both Pia’s pubic area and her left breast.

8. September 8, 1985 (San Casciano):

French tourists Jean-Michel Kraveichvili (25) and Nadine Mauriot (36) were camping in a small tent. The killer slashed the tent open, shot them both, and mutilated Nadine. Days later, state prosecutor Silvia Della Monica received a chilling piece of mail. Inside an unmarked envelope was a medical flap containing a piece of Nadine’s breast tissue. The Monster was officially taunting the police.

The Sardinian trail

How do you catch a ghost? The Italian police started by looking at the very first murder in 1968.

When Barbara Locci and Antonio Lo Bianco were killed, police quickly zeroed in on Barbara’s husband, Stefano Mele. Stefano was a sickly, mild-mannered farmhand from Sardinia. After hours of grueling interrogation, he confessed. He was sent to prison. Case closed, right?

Wrong.

While Stefano was sitting in a prison cell, the exact same .22 caliber Beretta was used to commit the 1974 murders. The police panicked. They realized Stefano couldn’t possibly be the lone killer. This sparked the “Sardinian Trail” (Pista Sarda) phase of the investigation.

Detectives discovered a web of Sardinian immigrants living in Tuscany. Barbara Locci had multiple lovers, including a tough, violent man named Francesco Vinci. Police theorized that Stefano didn’t act alone. Maybe he hired Francesco. Or maybe Francesco stole the gun. Authorities began arresting various members of this tight-knit community. They locked up Francesco Vinci. They locked up his brother, Salvatore.

The plan backfired spectacularly.

Every single time the police put a prime Sardinian suspect behind bars, the Monster struck again, mocking their efforts. By 1989, a judge forced the prosecution to drop all charges against the Sardinian men. The Beretta pistol was never found. The trail ran ice cold.

Pietro Pacciani and the Country Bumpkins

The investigation into the Monster of Florence has spawned numerous films and series, including Netflix’s Il Mostro. Source: Netflix

By the early 1990s, the public demanded answers. The pressure on the Florence police department was staggering. They formed a specialized anti-monster task force. An anonymous tip led them to a man named Pietro Pacciani.

Pacciani was a terrifying figure. He was an incredibly violent farmer with a history of sexual assault and domestic abuse. Back in 1951, he had caught his fiancée with a traveling salesman. Pacciani stabbed the man to death and forced his fiancée to have sex with him right next to the bleeding corpse. He served 13 years in prison for the crime.

When police raided Pacciani’s farmhouse, they found a single Winchester .22 caliber bullet stamped with an “H” buried in his garden. It was the smoking gun they desperately needed.

Prosecutors painted Pacciani as a bloodthirsty brute. In 1994, he was convicted of seven of the eight double murders and sentenced to life in prison.

But the case was built on a house of cards.

During the appeal process in 1996, defense attorneys shredded the prosecution’s evidence. The bullet found in the garden looked entirely pristine, suggesting it was recently planted rather than buried for a decade. The court acquitted Pacciani and ordered a retrial.

Realizing Pacciani couldn’t have pulled off the complex logistics alone, the prosecution pivoted. They found two of Pacciani’s friends: Mario Vanni, a former postman, and Giancarlo Lotti, a man with significant intellectual disabilities. During an interrogation, Vanni casually mentioned that he and Pacciani were just “compagni di merende” (snack buddies) who liked to eat bread and sausage together. The Italian press latched onto the nickname instantly.

Lotti eventually cracked. He confessed that he, Vanni, and Pacciani committed the murders together as a team. Vanni and Lotti were convicted in 2000.

Did they actually do it?

Most experts heavily doubt it. Pacciani died of a sudden, mysterious heart attack in 1998 before his second trial could begin. Many believe Lotti was a highly suggestible man coerced into a false confession by aggressive police tactics. Zero DNA, fingerprints, or physical evidence placed the “Snack Buddies” at any of the crime scenes. The missing Beretta was never recovered.

The absolute absurdity of the Pacciani trials continues to captivate the public. It is so chaotic that Netflix began filming Il Mostro: Pietro Pacciani in mid-2026 to chronicle this exact circus of justice.

The Cult of the Red Rose: Were body parts harvested?

If a group of aging, bumbling farmhands didn’t pull off these surgical precision strikes, who did?

A very dark theory emerged in the late 90s. Some investigators suggested the Monster wasn’t a single person, but an esoteric sect of wealthy doctors, pharmacists, and aristocrats. This group, rumored to be called the “Cult of the Red Rose,” supposedly paid massive sums of money for female body parts to use in black magic rituals. Pacciani and his friends were allegedly just the grunts hired to do the dirty work.

This theory gained dangerous traction after the suspicious death of Dr. Francesco Narducci, a wealthy gastroenterologist from Perugia. Narducci’s body was found floating in Lake Trasimeno shortly after the final Monster murder in 1985. His death was quickly ruled a drowning. Years later, his body was exhumed, and autopsies suggested he might have been strangled. Rumors swirled that Narducci was the cult’s mastermind, murdered to keep the sect’s secrets buried.

While it sounds like a Hollywood thriller, no concrete evidence ever linked a satanic cult to the murders. It remains a fascinating, albeit unproven, diversion.

The Zodiac killer connection: Did the monster move to italy?

Public domain.

If you are not already dizzy, buckle up. The most explosive theory surrounding the Monster of Florence requires you to look across the Atlantic Ocean.

Between 1968 and 1969, a serial killer calling himself the “Zodiac” murdered at least five people in Northern California. He wore an executioner’s hood. He taunted the police with coded ciphers sent to local newspapers. He targeted couples parked in secluded lovers’ lanes.

Then, after 1969, the Zodiac abruptly vanished.

Five years later, in 1974, the Monster of Florence began his terrifying reign of mutilation across Italy (discounting the anomalous 1968 Sardinian murder). Is it possible they are the exact same man?

Enter Giuseppe “Joe” Bevilacqua

In 2018, an Italian investigative journalist named Francesco Amicone dropped a bombshell. He published a series of articles claiming he had identified both the Zodiac and the Monster of Florence. The man he pointed to was Giuseppe “Joe” Bevilacqua.

Bevilacqua was born in Italy in 1935 but emigrated to the United States. He joined the US Army and served in the Criminal Investigation Division (CID). His military assignments placed him in Northern California during the exact timeframe of the Zodiac killings.

In the summer of 1974, Bevilacqua moved to Florence, Italy, after securing a prestigious job: Superintendent of the Florence American Cemetery and Memorial. Just two months after he arrived, the Monster of Florence committed his first mutilation murder.

Amicone didn’t just point fingers based on geography. He claimed that Bevilacqua actually confessed to him during a series of private conversations in 2017. According to Amicone, the former military man admitted his guilt to clear his conscience, allegedly stating, “I am the monster of Florence… I didn’t turn myself in so as not to get others into trouble”.

The Cryptic Evidence

Amicone dug deep into the unsolved Zodiac ciphers. He claims that applying a specific cryptographic key to the famous unsolved Zodiac “My Name Is…” 13-character cipher clearly spells out Bevilacqua’s identity.

The physical clues are equally haunting.

• The Footprints: The Zodiac Killer notoriously wore military-issue Wing Walker boots during his attack at Lake Berryessa. Italian forensic teams discovered boot prints at several Monster of Florence crime scenes that closely matched similar military-grade footwear.
• The Water Motif: The Zodiac actively hunted near bodies of water (Lake Herman Road, Lake Berryessa, Riverside). The Monster of Florence displayed a very similar geographical quirk. Almost all the Italian crime scenes were located near small rivers, streams, or lakes.
• The Taunts: Both killers needed the spotlight. The Zodiac sent bloody shreds of victim Paul Stine’s shirt to the San Francisco Chronicle. The Monster of Florence sent a horrific piece of Nadine Mauriot’s breast tissue to the state prosecutor.
• The Witness: Believe it or not, Giuseppe Bevilacqua actually testified at the 1994 Pietro Pacciani trial. He lived near the site of the 1985 San Casciano murder and claimed he saw a suspicious man lurking in the woods days before the killings. Some theorists believe a classic serial killer move is injecting oneself into the investigation to monitor the police.

Why the Zodiac Theory makes sense (and why it doesn’t)

When you lay the facts side-by-side, the Zodiac/Monster connection feels incredibly persuasive. You have a highly trained military investigator capable of erasing his tracks, moving between two continents right as one killing spree ends and another begins. The psychological need to hunt couples in cars bridges both continents.

But criminal profilers throw up massive red flags.

The Zodiac Killer was fundamentally a domestic terrorist. He craved the media. He wanted front-page headlines and openly threatened to blow up a school bus. His primary weapon was fear.

The Monster of Florence operated entirely differently. He was a sexually motivated sadist. He didn’t want the media’s attention; he wanted the visceral thrill of mutilating his victims. He stayed completely silent in the shadows for 17 years, only mailing a single letter at the very end of his run.

Killers rarely change their core signatures. A man who shoots people for publicity in 1969 doesn’t typically evolve into a silent, surgical butcher in 1974. Furthermore, law enforcement agencies in both the US and Italy have never formally charged Bevilacqua, heavily suggesting Amicone’s evidence remains circumstantial or purely speculative.

Will we ever know?

The Monster of Florence case is a graveyard of ruined lives, botched investigations, and wild goose chases. The .22 caliber Beretta remains hidden. The DNA profiles pulled from the envelopes have never matched anyone in the system.

Whether the killer was a brutal Sardinian lover, a deeply disturbed farmer named Pietro Pacciani, a satanic cult leader, or a relocated American Zodiac, one fact remains absolute. The true mastermind got away with it. He stopped when he wanted to stop. He vanished back into the Tuscan countryside, leaving a legacy of blood that still haunts Italy today.

What do you think actually happened in those Tuscan hills? Do you buy the Giuseppe Bevilacqua Zodiac theory, or were Pacciani and his “Snack Buddies” really the ones pulling the trigger? Drop your thoughts, theories, and questions in the comments below.