The Zack Addy Storyline Bones Fans Still Don't Understand

"Bones" had a truly impressive run from 2005 to 2017, delivering 12 seasons of off-kilter procedural action and developing a dedicated fanbase in the process. That said, it took a little time for "Bones" to reach its full ratings potential. In fact, it wasn't until the fourth season, after Fox moved the show to the 8pm Thursday night slot, that it really took off. The series brought in an average of 10.81 million viewers for season 4, a marked improvement on the 8.9 million from the prior season. But season 4 could have easily been the point at which fans turned on "Bones," after a twist that truly nobody saw coming and which left fans feeling let down by the show they'd come to love.

Throughout its run, "Bones" managed to bewilder fans on several occasions. The "Bones" season 1 opening credits had viewers mixing up two cast members, and later David Boreanaz's Agent Seeley Booth had a whole storyline that to this day makes little sense. But no storyline has been met with more controversy than that of Zack Addy's (Eric Millegan) character arc, which included a confounding plot twist that actually played out towards the end of season 3, right before "Bones" made the move to Thursday night in an attempt to increase its viewership.

The major season 3 twist saw Addy, who had become a fan-favorite character by that point, suddenly cast in a grim new light. Millegan's character had been with the show since the first season, but the third season saw him ignominiously ousted from his main cast spot. Now, you don't stay on the air for 12 seasons without at least keeping fan expectations in mind a little. But it seems in this case fans still don't understand what happened with Zack Addy in "Bones" season 3.

When "Bones" started in 2005, Emily Deschanel's Temperance Brennan was supported by her team of interns, affectionately dubbed "squinterns" — an idea brought to "Bones" by a real detective. One of these squints — so named for the way in which scientists squint closely at their work — was Zack Addy, an awkward but lovable member of the "Bones" ensemble who struggled with social situations but was highly intelligent and seemingly a good guy at heart. In season 2, Addy completed his doctorate in forensic anthropology and became a forensic scientist at the Jeffersonian Institute, once again working alongside Brennan and the team.

All seemed to be going quite well for Addy and Eric Millegan, who had been a main cast member throughout two full seasons of "Bones," and remained so going into the third season. But the end of season 3 contained a shocking twist that revealed Addy had been working as an as an apprentice to the cannibalistic serial killer known as the Gormogon (Laurence Todd Rosenthal).

David Boreanaz might have thought the Gormogon storyline was just "bad TV" but most viewers were more concerned with their beloved Addy suddenly being revealed as a lackey for one of the series most disturbing killers. Aside from being a shock, what proved to be the most controversial twist in "Bones" history also didn't make a whole lot of sense.

Eric Millegan had a great run on the first three seasons of "Bones," becoming what seemed like an indispensable part of the Jeffersonian team. Initially refusing to complete his doctorate so that he could continue assisting Temperance Brennan, he eventually gained his PhD and even came face-to-face with Brennan's real-life counterpart when author Dr. Kathy Reichs played one of the professors reviewing Zack Addy's PhD thesis. After that, he seemingly secured his place as main cast member when his character landed a job at the Jeffersonian alongside his former boss and became one of the most beloved members of the team due to his warmth, compassion, and intelligence. Otherwise, Millegan even underwent what was essentially a "Bones" rite of passage when he was extra grossed out by a body on the show ("Bones" had some of the most upsettingly detailed cadavers yet seen on the small screen).

But things took a sudden turn at the end of season 3 when it was revealed that Addy had been working with the serial killer known as the Gormogon all along, leaving fans stunned. There's no shortage of incredulous reactions to Addy's big reveal online, with one Redditor claiming the producers "tossed him aside" and "insulted his intelligence by having him apprenticed to a cannibal." Commenters also claimed that "Bones" "wasted this character," while another Redditor put it succinctly when they 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." Even Millegan himself didn't seem too fond of his character's storyline, telling TV Guide "It wasn't my choice – it was a creative decision to shake things up and make a good season finale."

In reality, the big season 3 twist came as the result of a writers' strike, which forced the "Bones" writers to come up with a hasty way of wrapping up the season's storyline. Addy, it seems, became the solution, much to the dismay of fans everywhere. Still, the character returned as a guest multiple times in seasons 4 and 5, before making a full return in the 12th and final season — no doubt as a result of fan outcry over the nonsensical season 3 plot twist.