Bosch and Bosch: Legacy are two Amazon Studios TV crime series that follow Detective Hieronymus "Harry" Bosch, a character first introduced in the crime books written by Michael Connelly. The Bosch book series follows Harry Bosch as he works as a homicide detective for the LAPD before resigning and becoming a private investigator, much like the TV adaptations. And throughout the many seasons of Bosch and Bosch: Legacy, several books in the Bosch book series have been the source of inspiration. However, while Bosch and Bosch: Legacy are both based on the Michael Connelly crime novels, the storylines and character arcs can be quite different in the TV series. And one specific storyline that was completely changed for the TV adaptation is the story about the murder of Harry Bosch's mother.

Marjorie Phillips Lowe was Harry's mother, who was killed when Harry was only eleven years old. By the time the TV and book series start, Harry is already an adult working in the LAPD, and he is still haunted by what happened to his mother, even if he can't admit it or work through it yet. Bosch Season 3 and Season 4 are where Harry delves deeper into what happened to his mother and who killed her, until he gets the killer to confess in the Season 4 finale, bringing closure to Marjorie Lowe's murder case. But the storyline in the Michael Connelly novels is completely different, with the TV series even going as far as to change who killed Harry's mother. So, who exactly killed Harry Bosch's mother, and why was the story so much better in the books?