Sly Cooper is a master thief who has descended from a long line of other master thieves. His family has kept all their thieving secrets into one book simply known as, The Thievius Raccoonus. However, at the age of 8, Sly's home was ransacked by a horrible gang known as the Fiendish Five. The murdered Sly's family, and stole the Thievius Raccoonus, splitting the pages among themselves so that they themselves can overshadow the Cooper name as the greatest thieves. Sly was sent to an orphanage where he met Bentley and Murray, his lifelong friends and family. As Sly came of age, he began preparing and training to avenge his parents, steal back the Thievius Raccoonus, and bring down the Fiendish Five. As Sly stole his case record from the lovely inspector Carmelita Fox, he was shocked to discover that just a little over two years ago, all members of the Fiendish Five Mysteriously vanished without a trace. All of their last known sightings were at the Krakarov Volcano. In order to track them all down, that's where they are headed. After tracing the Fiendish Five's footsteps perfectly, they all find themselves in a strange new world, one that is dominated by one species, ponies. Sly and his gang soon learn that in this land's greatest treasure and weapon is stolen, the Elements of Harmony. Sly will need help from the inhabitants to get back the Thievius Raccoonus, while the group of Ponies he and his gang have befriended will need them to get back the Elements of Harmony.