Politiet finder en død mand i en parkeringskælder, og finder et motiv til mordet. Det viser sig, at offeret, hans kollega og en teenagepige var involveret i et trekantsdrama.

Dark Minds brings together the sharp criminal minds of author and investigative journalist M. William Phelps and pre-eminent criminal profiler John Kelly to reopen unsolved homicides thought to be the work of serial killers. They are assisted in their efforts by a source known only to viewers as "13," a convict serving multiple life terms for a series of murders, who presents his theories about potential motivations behind these chilling cold cases based on his own experiences. They bring fresh eyes to unsolved serial killer investigations using the combined instincts of three unique perspectives, with hopes that it will encourage viewers to bring forward new leads.

Sergio hasn't spoken since the day he murdered his parents. Six years later, a teen girl may be the key to revealing the whole story.

Sex and murder are often tied together in criminal investigations; and detectives uncover dirty secrets, scandalous sex affairs, online sex addictions, jealousy and stunning twisted fantasies when looking for motives for murder.

In the summer of 1995, two vulnerable teenage girls are accused of murdering their schoolteacher. For seventeen years, the two girls go their separate ways, Poppy having been charged with the murder. Fast-forward to modern day. Happily married mother Serena is now back in the same seaside town for the first time as she cares for her dying mother Rachel. Poppy is living in quite different circumstances. Having served seventeen years for a crime she still insists she didn’t commit, she has only one thing on her mind… the truth. And if she didn’t kill Marcus, then who did?