On Feb. 20, 1976, freshman John Zera disappeared from a high school in suburban Milwaukee. In the early days, John's family hoped for his safe return. Later, they prayed whoever was responsible for his disappearance would be brought to justice. Finally, they clung to hope that advances in technology or someone with a guilty conscience would someday offer an explanation of what happened to their Johnny. And why.

In this episode, Milwaukee Journal Sentinel reporter Gina Barton looks at how the case began and what drew her to it.

For more information on the true crime series Unsolved: A murder mystery podcast, visit http://usatoday.com/unsolved.

For more reporting on cold cases, unsolved cases and true crime detectives, as well as additional true crime stories and investigative journalism visit witness.usatoday.com. Crime reporter and investigative reporter Gina Barton is also host of Untested: A true crime podcast, in which Annie Harrison joins the rank of true crime detectives as she solves the cold case of a possible serial rapist. Subscribe to Untested: A true crime podcast at https://art19.com/shows/untested

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