Penelope Garcia is the wizard of the computer, while Kirsten Vangsness and A.J. Cook are JJ. Dr. Spencer Reid is the genius, played by Matthew Gray Gubler, and Morgan Derek is portrayed by Shemar Moore. The original cast of Criminal Minds was composed of the best profiler in the Behavioral Analysis Unit, Jason Gideon, played by Mandy Patinkin. Over the years, it has become one of the most successful crime series on American television and a staple of the genre.
After the second season, when Patinkin departed from the series, the cast unexpectedly underwent a lineup change. The writers hurriedly searched for a believable narrative explanation, as the absence of the Tony-award-winning actor created a significant void in Criminal Minds, the main character.

Mandy Patinkin himself points out that he decided to leave the show Criminal Minds due to “creative differences.” It was reported that the actor quit because of these differences. In a statement released by CBS in 2007, it was stated that there were no salary issues or contract renegotiations to be done, and Patinkin was asked to be released from his role. This happened at the time when he was with ABC.
In a later interview with New York Magazine in 2012, Patinkin spoke about the events of the show, explaining that the biggest mistake of his public career was signing on to play Jason Gideon, as he didn’t expect it to feature as much violence as it did.
“I never thought they were going to kill and rape all these women every night, every day, week after week, year after year.”
Patinkin confessed that appearing on shows like The Good Fight and Homeland didn’t go as expected for him as an actor, and he feared that it would permanently damage his television career. He referred to the experience as “destructive” to his personality and soul, which is why he considered quitting.
How did the Criminal Minds writers explain Gideon’s sudden exit?

He felt responsible for sending six men into a warehouse containing a bomb that would kill them all – a mission gone wrong. After struggling with post-traumatic stress disorder, he comes back from medical leave. He was written as a dedicated FBI agent who took his job incredibly seriously, starting from the first season. The reasons for Gideon’s exit mirrored Patinkin’s own predicament, fittingly.
Throughout Gideon’s run on the show, he would blame himself for the terrible things that happened to the people and colleagues in his life, where he dealt with similar experiences, and proved to be too much for Frank Breitkopf, the serial killer responsible for the death of his new girlfriend Sarah, pushing him out of his profession.
In the final scene of the second episode of the third season, Mandy Patinkin returned to film a scene in his cabin. Reid, who looked like Gideon’s protégé, finds a letter when he looks for him. In the letter, he finds everything but a badge and a gun. He explains that he is leaving to search for a new meaning in his life. When he first met Sarah, it seemed right and he had that belief. He believed in happy endings. He believed he had to go back to college.
In the 1978 episode of Criminal Minds, titled “Savage Ben,” the character played by Joe Mantegna, David Rossi, features in flashbacks to his time in the BAU. Prior to this, Gideon had investigated alongside his partner, Donnie Mallick, for 30 years, who was later revealed to be a serial killer and was off-screen murdered. In the final scene, as Gideon leaves a diner in Nevada, the waitress asks him where he’s headed, to which he replies with the phrase “Particular in nowhere.”