In the Season 3 finale of “Bones,” Brennan and Booth shockingly discover that Zack has secretly been aiding the serial killer Gormogon. During this time, the two leads had been working tirelessly to uncover the efforts of the cruel cannibalistic murderer, only to disturbingly stumble upon the revelation that Zack had been his apprentice. Soon after, Zack is placed in a psychiatric facility after pleading insanity.
For many fans, the narrative’s reveal lacked internal logic, particularly because Zack had consistently demonstrated a deep warmth and compassion for his peers. His sudden transformation into a devious and heartless apprentice felt random and wholly out of character. Reddit u/Apprehensive_Lack418 wrote, “I cannot see how this character who has a soft spot for his family, was really affected by the death of a child and expresses sadness and loneliness that he cannot connect with neurotypical people became a serial killer’s apprentice.” Moreover, the plot point’s hurried introduction marred any kind of well-earned resolution, leaving viewers confused. In a 2008 interview with TV Guide, even actor Millegan distanced himself from the storyline, saying, “It wasn’t my choice. It was a creative decision to shake things up and make a good season finale.”
While “Bones” gained a reputation for taking narrative risks, Zack’s curtailed arc on the series remains a sore point for fans who had been hoping to witness a more compelling character evolution for the beloved young doctor.