Clockwerk formed the Fiendish Five and attacked Sly's home, killing his father and stealing the Thievius Raccoonus. The Fiendish Five went their separate ways, with Clockwerk not interfering directly with the other members, although he did provide advanced technology. His name was not known to Sly and his friends, until Sly began to notice a strange bird-shaped silhouette in the background on the pages of the Thievius Raccoonus.
It wasn't until Sly visited the Krack-Karov Volcano, where Clockwerk had been residing, that Sly found out the true identity of the final member of the Fiendish Five. He used a giant death ray to try and stop the Cooper gang, as well as even capturing Carmelita Fox and using her as bait. In the end, Sly defeated Clockwerk, even with the help of someone like Carmelita.