Why did prentiss leave

8 มี.ค. Nonetheless, there are no reports of Brewster leaving the show again. And our boy Reid did a fine job convincing Prentiss to stay. 26 ก.ค. Penelope was a massively popular asset to the BAU but at the end of season 15, she took on a new challenge and left the office for good. 27 มิ.ย. Despite the character becoming an integral part of the Behavioral Analysis Unit (or BAU), Prentiss left the squad at the end of the seventh.