Well, my top 5 always changes from day to day. So, my top 5 for today would be:
1. Lady Heather's Box (Season 3) - Lady Heather, Eddie, Lindsey, Cath/Sara angst, and Marg at her best.
2. Caged (Season 2) - One of the first times we see Cath & Sara together. Plus, I like both of the cases.
3. BTK2 (Season 7) - Once again, Marg doing what she does best. The inclusion of both Lindsey & Sam puts this one high on my list (even though I'm still pissed that they killed Sam). Then there's Danny Bonaduce & the mini crime scene.
4. No Humans Involved (Season 5) - IMO, the best episode that shows the compassionate side of Sara - yes, even more than the Sara-specific episodes of Committed, Nesting Dolls, and Empty Eyes - because it's so much more subtle. Her comment to Brass at the end -"Go with the living, Jim. The dead can wait" - is so poignant. Also, you get a look at Greg out in the field, being there during a shooting, finding the boy in the container, etc. Makes for a wonderful episode. And can't forget Gil's "Miss Piggy" (or is it MR Piggy?) gift to Catherine.
5. A tie for fifth place:
(A) Kiss Kiss, Bye Bye (season 6) - Scott Wilson & Faye Dunaway. Cath confronting Sam in the limo, the return of Lily (Cath's mom), Greg grumbling about Grissom not accepting the food offered by Lois, the return of Mr Jensen...
(B) The Good, The Bad, & The Dominatrix (season 7) - a different side of Lady Heather. Catherine's ramble to Sara about Gil's fascination with LH, Sara meeting LH, Joe Penny, the cab dispatcher hoping Nick & Warrick were from Strip-O-Gram, Judy getting a bit longer part than normal, Cath calling Gil a hypocrite.