The team gets faced with one of the most challenging cases yet. It involves one of the most viscous unsubs they've ever worked with, Mr.Scratch. The team has no other choice but to ask for help from one of their old coworkers and friend. It's a tough decision to make but he agrees to come back if it'll help save the missing member of their team which is their unit chief, and his old friend, Emily Prentiss. Although he believed going into hiding was the best option for him and his son, he also couldn't let Emily be tortured over something that was his fault.