The crime itself was very interesting and a great twist to who the UnSub was (like many others, I believed it was the first victims son Also quite believable as to why the man would take up where the first UnSub left off.
Best part about this episode though (as a huge Rossi fan) was the story between the old sheriff and Rossi. We find out the significance of the bracelet that Rossi carries with him (first seen in the episode where Rossi makes his debut. At the end when Rossi tells the Sheriff it's been 21 years, the Sheriff tells him "Don't let it get to 22" That leads beautifully into the upcoming episode "Damaged"
Anything to do with Rossi is golden with me :)