'Criminal Minds' comes to an emotional end with visits from past characters

After 15 seasons, Criminal Minds came to an end Wednesday night. The procedural FBI drama has been a cornerstone of CBS's primetime night lineup since 2005.

The show treated fans to flashbacks of some of their favorite characters who are no longer with the show, and even brought back a few as guest stars. In one of the plot lines, Dr. Spencer Ried (Mathew Gray Gubler) suffers a brain hemorrhage and hallucinates the return of Chief Strauss (Jayne Atkins), Maeve Donovan (Beth Riesgraf) and George Foyet (C. Thomas Howell).

The finale also teased a budding romance between Luke Alvez (Adam Rodriguez) and Penelope Garcia (Kirsten Vangsness). Garcia is starting a new job at a "non-profit," which leads to Alvez asking her out to dinner.

The response to the finale on Twitter was immense. The show was trending all night as fans celebrated the end of a long journey.

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