Back from the prologue, the Cooper Gang help save Sly's life and Sly goes into the Cooper Vault.
- Arc Villain: Dr. M.
- Amnesiac Villain Joins the Heroes: Downplayed. Sly claims to have amnesia at the end, and Carmelita tells him that he's her partner.
- Death Course: The Cooper Vault. The entire place was create so that only a Cooper could navigate it, so thieves who know the various techniques of the Cooper lineage are able to navigate its many traps.
- The Reveal: Dr. M. was the brains of the previous Cooper Gang. Sly's father's gang, that is.
- Signature Move: It is revealed that Sly's father perfected the ability rail-slide on lasers, having died before he could name it and admit it into the Thievius Raccoonus.
- Title Drop: The game is called "Honor Among Thieves".