As the investigation unfolds, the BAU discovers the kidnapper is , Cat's former cellmate. The team initially believes the hostages are Cat’s biological relatives, but the truth is much darker:
The hostages are rescued, Juliette is arrested, and Cat is sent back to death row, having failed to truly come between Reid and his new life. Criminal Minds Season 15 Episode 6 Recap: Date Night
The father and daughter are actually Maxine’s father and sister .
The situation reaches a boiling point at Reid’s apartment. In a surprising turn, herself steps into the fray. Using her own history of trauma, she outmaneuvers Cat by convincing her she has broken Reid’s spirit, eventually tricking Cat into sending a text that reveals the hostages' location.
Cat orchestrated the entire event to prove to Maxine that Reid isn't the "nice guy" she thinks he is. The Resolution