In August 1992, 21-year-old Tammy Zywicki set out on a routine drive back to college after dropping off her younger brother at Northwestern University. Somewhere along Interstate 80 in Illinois, her car broke down. Witnesses saw Tammy waiting on the shoulder and speaking with the driver of a semi-truck. By the next day, both she and her car were gone.

A week later, Tammy’s body was found nearly 500 miles away in Missouri. She had been stabbed multiple times and wrapped in a blanket that didn’t belong to her. Despite eyewitness accounts, physical evidence, and decades of investigation, her killer has never been identified.

In this episode of Find My Killer, we explore the haunting case of Tammy Zywicki—her life, the final hours on the highway, the suspects, and why this case remains unsolved more than thirty years later.

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