Jason Gideon was murdered.
The team was called to a cabin, only to discover that Jason Gideon—who served as a key member of the BAU in Seasons 1 through 3—had been shot dead. Luckily, he left behind a series of clues meant to help the team finally catch the one UnSub that had alluded him his entire career.
(Season 10, Episode 13, "Nelson's Sparrow")
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