More often than we’d like to believe, people get away with murder. As cases grow cold, cops retire. Witnesses die. Evidence disappears. Unsolved, a true crime podcast series from USA TODAY and the Milwaukee Journal Sentinel, guides listeners through these real-life mysteries, uncovering new clues along the way.

Season four of Unsolved delves into the disappearance of Alexis Patterson, a 7-year-old girl who disappeared on her way to school in 2002. At first, there was a massive search and sympathy for her family, but that quickly changed as her parents became suspects. Over the years, there have been conspiracy theories and false leads and cases of mistaken identity. Still, her mom has never given up hope that Alexis will come home again someday.

Season three of Unsolved tells the story of Father Alfred Kunz, whose throat was slit inside St. Michael School in 1998. Some believe his death was linked to his battles against evil. Others believe his all-too-human flaws were to blame.

Season two of Unsolved, released in 2017, examines the case of toddler Michelle Manders, who vanished from her bedroom in the middle of the night in 1981. Did she wander alone into the darkness? Or was she kidnapped?

Season one of Unsolved, released in 2015, explores the circumstances surrounding the death of 14-year-old John Zera, who disappeared from Franklin High School in 1976. The seven episodes follow investigators through decades of dead ends as they hold on to hope of finding the killer.

Subscribe to Unsolved on Apple Podcasts, Stitcher Radio or wherever you get your podcasts. For more information on the series, visit usatoday.com/unsolved.