Damon Gupton is leaving Criminal Minds after one season.

Gupton, who was brought in as Special Agent Stephen Walker in Season 12 after Thomas Gibson's dismissal, revealed on Twitter over the weekend that he lost his job.

There's been a lot of cast shake-up on the long-running CBS crime drama over the last season. Along with Gupton joining in the middle of the season, Adam Rodriguez joined the BAU at the start of Season 12, then Gibson was fired, then Aisha Tyler joined the cast full-time, then Paget Brewster re-joined the show. And it might not be over yet: A.J. Cook and Kirsten Vangsness are locked in salary negotiations with the network seeking parity with their male co-stars Joe Mantegna and Matthew Gray Gubler, and are willing to walk away if they don't get it.

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Gupton never quite fit in with the show, and Criminal Minds showrunner Erica Messer has said that hiring Gupton was the network's decision. It seems safe to say that Walker will be one of the characters who didn't survive the crash that ended Season 12 on a cliff-hanger.

Damon Gupton, <em>Criminal Minds</em>Damon Gupton, Criminal Minds

Criminal Minds Season 13 premieres Wednesday, September 27 at 10/9c on CBS.

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