'Criminal Minds' 300th Episode: Why the Believers Cult Targeted the BAU

Criminal Minds' season 14 premiere uncovered the connection between the Behavioral Analysis Unit and the Believers cult involves a blast from the past.

The 300th episode of the CBS crime procedural connected their current predicament, which found Reid and Garcia in the grasp of the dangerous cult, with a case they solved back in season four.

Once they realize that agent Meadows (Karen David) was the mole within the FBI, they investigate further and see that she has been infiltrated in the agency for many years, covering up 299 murders from the BAU. To make matters worse, Reid is the religious cult's target for their 300th and final sacrifice.

When they attempt to realize why Meadows acted so comfortably with them before her cover was blown, Prentiss realizes that she had known her before.

"Oh my God, I have seen her, and so have you," she tells Rossi. "We have both met the Believes before... Liberty Ranch in Colorado."

Turns out that the Believers had been plotting their revenge against the BAU since they had a part in the death of their leader Benjamin Cyrus (Luke Perry), who came into the crossfires of the organization in season four's "Minimal Loss."

"Ben's Believers. Benjamin Cyrus and Benjamin Merva (Michael Hogan) are connected. And this is the payback for Cyrus' death."

At the warehouse where the Believers are hiding, Meadows tells Reid the team should've thought about how the Believers might retaliate ten years later, and that've learned from their mistakes and his friends will never find them. An unexpected commotion in the warehouse, however, gives Garcia the opportunity to escape and she rushes back to headquarters.

Knowing the connection to Cyrus proves key for the BAU to find the cult after they move to a different location following Garcia's escape. The team follows the cult to a remote area of Kentucky, where they are about to sacrifice Reid.

Just before they kill him, the FBI confronts the cult and they take out Merva and Meadows. The threat of the cult has been eradicated once and for all.

The whole experience leads Reid to reflect on his lack of expressing emotion in the past. He tells Prentiss that he hopes the team knows how much he loves them.

"That's the good thing about family, we already know," she tells the scientist as the team returns home safe and sound.

Criminal Minds airs Wednesdays at 10 p.m. ET on CBS.