During the early morning hours of December 29, 1991, a woman is murdered in a Phoenix bar. At the crime scene, investigators find a shoe-print, several foreign hairs, and unknown fingerprints. But they believe the most telling piece of evidence is the bite mark on the victim's chest. Based on his bite pattern, a local postman is charged, tried and convicted of murder, but he maintains his innocence. Ten years into his sentence, improved technology yields new information about old evidence, and earns him another trial.