Štefan Mlynarovič, who was known in prison by the nickname Johnny, has spent the majority of his adult life incarcerated. Throughout his early years he engaged in theft and repeatedly found himself in conflict with law enforcement. His criminal trajectory escalated to murder, and he was convicted of two killings, receiving a life sentence. After serving time for his first murder, authorities granted him a second chance and released him. Within less than a year of his release, he committed another homicide. In that later case the victim suffered nine stab wounds inflicted with a kitchen knife. Police have been unable to resolve a separate murder of a young girl that was linked to the same period.