Evolutionshowrunner and executive producer Erica Messer explains why one former main cast member won't return. Even though the crime drama recently wrapped up its third installment, Criminal Minds: Evolution season 4 is confirmed.

After another gripping season spent trying to unmask the serial killers on Sicarius’ deadly network, Criminal Minds: Evolution ‘s Season 18 finale finally identified The Disciple and put the puzzle pieces together — but not before several jaw-dropping twists that will have viewers on the edge of their seats.

Criminal Minds' finally brought the Voit mystery to an end  — so where does the show go from here after that season 18 ending?