'Criminal Minds' season 12 spoilers: game-changing Reid-centric episode teased

An upcoming episode of "Criminal Minds" season 12, episode 13 to be exact, will focus on everyone's favorite genius, Spencer Reid (Matthew Gray Gubler).

This one is sure to be big and game-changing especially because it is cast member Kirsten Vangsness who will co-write this exciting installment.

The actress, who plays Federal Bureau of Investigation (FBI) technical analyst Penelope Garcia in the series, is notorious for writing stories that mark huge and shocking changes for characters involved and the show itself. This "Criminal Minds" season 12 episode is no exception.

It was Vangsness who co-wrote the episode that marked Derek's (Shemar Moore) last day in the force. She also had a hand in the story that led to Gideon's (Mandy Patinkin) death.

Vangsness knows about her reputation very well. "I seem to co-write the episodes that change the course for people," the actress told TVLine.

In turn, she warns fans of what the Reid-centric "Criminal Minds" season 12 episode, which is very aptly titled "Spencer," will entail from the character.

"That does not mean the ends of people, it just changes their course," Vangsness continued, before adding, "So [Episode 13] is a course changer. It's a course changer," she went on to say.

While it does not look like Reid is not going to meet his end in this installment, the fact that "Criminal Minds" season 12, episode 13 has his name as the title suggests that fans will learn more about who the criminal profiler really is.

It also sounds like the episode is an ode to him. Based on the statement of Vangsness, fans might walk away from this "Criminal Minds" season 12 episode with a whole new perception or understanding of Reid. Perhaps fans will learn a side of him that the show is yet to show.

"Criminal Minds" season 12 every Wednesday at 9 p.m. ET on CBS.