“Bones” seems like the kind of cop show dreamed up by a network desperate to win the ratings war: Two attractive leads clash over their differing worldviews, with the logical, scientifically-minded Temperance “Bones” Brennan (Emily Deschanel) frequently at loggerheads with the more spiritually-inclined FBI agent Seeley Booth (David Boreanaz). But the show wasn’t just developed to appeal to audiences in the early 2000s. It’s actually based on the real-life anthropologist Katherine Joan Reichs.

Reichs was the author of 23 novels in the Temperance Brennan series, which is often believed to have inspired Bones. But Dr. Reichs herself was actually the main inspiration for the series, which ran for 12 seasons on the FOX network between 2005 and 2017. Series creator Hart Hanson confirmed that he was influenced by the real-life forensic anthropologist when conceiving Bones and has since incorporated certain events from her life into the series. A scene from the Bones pilot episode was taken directly from Reichs’ real-life experiences, and the doctor herself served as a producer throughout the series’ run, even writing some episodes herself.

So it makes sense that Hanson gave Reichs his own cameo, but it was so subtle that fans of the series may have missed it.

In season 2 of Bones, Dr. Kathy Reichs appears in the episode “Judas on a Pole” as, you guessed it, a doctor. Specifically, she played Professor Constance Wright, who sits on the panel that reviews Zack Addy’s (Eric Millegan) dissertation. Before earning his PhD in forensic anthropology, Addy was Temperance Brennan’s assistant, but during the panel meeting she found herself face to face with his boss and her real-life inspiration (Zack Addy eventually left the show after season 3 and returned sporadically). Reichs even has a few lines in her brief appearance before Agent Booth kidnaps Dr. Brennan and the scene ends.

In the book Bones: The Official Companion, Reichs reflected on her performance, saying, “I had a great time. I told Hart Hanson he may have created a monster because I was having a really good time.”

Unfortunately, this was Reichs’ only cameo appearance in the entire 12-season run, but it certainly wasn’t her last contribution to the series overall. In addition to serving as a producer, she wrote the season 5 episode “The Witch in the Wardrobe,” the season 9 episode “The Dude in the Dam,” and co-wrote the season 10 episode “The Woman in the Whirlpool” and the season 11 episode “The Stiff in the Cliff” with her daughter Kerry Reichs.