This is the Zodiac…

We examine the shocking real-life crimes given the Hollywood treatment

On 1 August 1969, a letter arrived at the offices of the San Francisco Chronicle.

In it, a killer boasted he’d murdered three teenagers in northern California.

The first were Betty Lou Jensen, 16, and David Faraday, 17. The couple had been huddled in a car near Lake Herman at 11.15pm on 20 December 1968, when the car was peppered with bullets.

Then, in July 1969, Darlene Ferrin, 22, and Michael Mageau, 19, were parked in the Blue Rock Springs Golf Course, Vallejo.

The killer pulled up, got out of the car and opened fire.

Michael survived, describing the attacker as 5ft 8in, heavy-set.

Almost identical letters had been sent to two other local newspapers. To prove this, I shall state some facts which only I and police know, the killer wrote.

He then described the crime scenes, weapons, position of the bodies.

10 shots fired. Boy was on back, feet to the car, he wrote of the Lake Herman murders. Boy was also shot in knee, he wrote of Michael Mageau. The letters contained coded ciphers he claimed contained clues to his identity, along with a demand they be printed on the front page.

Or he’d spend the weekend killing.

The ciphers were printed – yet not on the front page.

The threatened murders didn’t happen, but on 7 August another letter arrived.

Dear Editor, this is the Zodiac speaking… it read.

It provided more details of the murders – and the killer had given himself a name.

The Zodiac.

Two days later, one of the ciphers was cracked by an amateur cryptographer.

It revealed a rambling message on the joys of murder.

I like killing people because it is so much fun, it read.

The unknown serial killer was taunting police, too. Hours after the Blue Rock Springs shootings, an anonymous caller had reported the crime to police, also confessing to the Lake Herman murders.

In September 1969, Bryan Hartnell, 20, and Cecelia Shepard, 22, were enjoying a picnic by Lake Berryessa when they were held at gunpoint by

a man wearing a strange executioner-type hood.

He had a symbol on his chest – a circle intersected by a cross, like the crosshairs of a gun.

The man demanded money and their car.

But after tying them up, he stabbed them with a knife.

Before he left, he drew the same symbol on the car door, and an inscription ending with the words by knife.

Again, police received an anonymous call from a man admitting to the attack.

Bryan miraculously survived and was able to describe his attacker.

The people of San Francisco and its suburbs lived in fear.

It was believed the Zodiac killer was targeting young lovers meeting in secluded areas.

But then, on 11 October, taxi driver Paul Stine, 29, picked up a man who gave an address in Presidio Heights, San Francisco.

Only, as the driver approached a junction, he was shot in the head by his passenger.

A blood-soaked section of his shirt was torn off. Two days later, part of this was sent to the Chronicle, along with another letter from the Zodiac killer.

Then there were notes containing threats of bombs, explosions and the slaughter of schoolchildren.

This led to widespread fear and panic.

The Zodiac continued to taunt the media and the San Francisco Police Department (SFPD). Sending letters, maps, ciphers, threats.

And claiming responsibility for more murders.

He’d sign off letters with a number – thought to indicate his tally of victims.

Zodiac – 12, SFPD – 0.

Murders carried out earlier in the 1960s were rumoured to be his work.

Yet, Paul Stine was the last confirmed victim of the Zodiac.

Police interviewed many suspects, but only seriously investigated one – Arthur Leigh Allen, who maintained his innocence.

The last known letter was postmarked 29 January 1974.

And despite attempts of military-grade cryptographers, only one of the ciphers has ever been cracked.

Scores of researchers are still investigating the murders.

Yet the Zodiac case remains unsolved, and it was closed in April 2004, only to be opened again in 2007.

The number of the Zodiac’s victims remains unknown.

But his final letter was signed: Zodiac – 37, SFPD – 0.

As the driver approached a junction, he was shot in the head