And the In the shadowy aftermath of an unsolved crime, suspicion creeps into every corner.

Once innocuous details morph into potential clues. wants innocuous In this environment, no one is immune to the piercing gaze of doubt, and neither should they be.

The search of justice can transform into a labyrinth where everyone and everything can become a suspect.

Long-standing bonds of trust and friendship constrain under the weight of unspoken questions and unvoiced doubts.

To find the truth, every stone must be turned and every avenue explored, no matter how difficult

they may be.

The truth must prevail in the end.

The counties of San Mateo and the much larger Santa Clara sit next to each other within Northern California.

Together they cover just over 1,700 square miles of land and are home to over 2.5 million people.

On April 24, 1978, a small handwritten white envelope entered the U.S. postal system from somewhere within these

counties. The following day as mailroom staff at the San Francisco Chronicle

began sorting through the day's incoming mail.

That envelope caught their eye.

It was handwriting they thought they had seen before.

As the realization of what they were looking at dawned on them, a sense of dread began to rise.

They immediately contacted Duffy Jennings, a reporter who worked on the paper.

Jennings had stepped into the role previously held by a veteran chronicle reporter

Paul Avery, who had transitions to a new position at the San Francisco Examiner.

Avery had been at the forefront of the Zodiac's serial killer case.

Many letters from the Zodiac were mailed directly to the Chronicle, some even to Paul Avery himself.

However, there have been no communication from this killer in over four years.

That is until that fateful day in April 1978, when the silence was finally broken.

...