Chicago PD fans were left stunned at the end of Wednesday night's episode when the show teased the unexpected return of a controversial character.
In the promo for next week's episode, it was revealed that villain Sean O'Neal will be making a comeback.
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The former addict (played by Yellowstone's Jefferson White), who is the son of Chief Patrick O'Neal, is currently serving a lengthy prison sentence for his involvement in a sex trafficking ring, which was discovered by Officer Hailey Upton in the midseason finale.
Taking to Twitter, viewers expressed their shock over his return, with one person writing: "Oh [expletive], that next episode preview! I didn't think we would see serial killer Sean again and so soon," while another added: "Not Sean back #ChicagoPD."
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A third viewer expressed their concerns, tweeting: "There's no way that Sean is normal after getting the back of his head shot off! I think he's gonna turn totally Psycho #chicagopd."
Jefferson White as Sean
The synopsis for the upcoming episode reads: "Sean O’Neal surprises Det. Upton with a call from prison, revealing sensitive information. While Upton grapples with how to keep O’Neal at a distance, the team quickly mobilizes to stop a crime in progress before it’s too late."
Showrunner Gwen Sigan spoke about the character and what actor Jefferson has brought to the role since joining the show in season 10.
"With Jefferson's role, we knew Sean was going to be the villain of the first half of the season, so we knew he was going to be in quite a lot," she told CinemaBlend. "We knew his relationship with Upton was going to be the crux of the story. But every time we got an episode turned in, and we would see what Jefferson did with it, it just inspired different elements. He became this character. I feel like Jefferson infused this cult leader [persona]."