Three different demos have been released for Sly Cooper and the Thievius Raccoonus.
This demo contains a playthrough of Raleigh's level. All missions here had alternate titles during development but were changed in the final release. Character dialogue was also different before the game was finalized. Some dialogue simply has not been included yet. Guards also had different designs.
E3 preview alpha
This demo, released in May 2002, contains an expanded playthrough of the game, featuring the entirety of "Tide of Terror" and most of "Sunset Snake Eyes," with the exception of the boss fight between Sly and Muggshot. Almost every mission had alternate titles, with "The Gunboat Graveyard" being the only exception. Among these alternate titles were all alternate titles used in the E3 demo. In addition, some of the guards had different designs (with those that had alternate designs retaining their designs from the E3 demo), though others instead had their finalized designs. Some of the dialogue had been finalized, whereas other pieces of the dialogue remain excluded and only visible with text.
There is a PlayStation 2 demo disc that contains only the first half of the Prologue. It was released exclusively for the 2002 Electronic Entertainment Expo. This demo features the early version of Carmelita Fox, who was originally known as Chase.