Their members consisted of:
- Clockwerk, a robotic owl - Founder and leader (deceased)
- Panda King, the name says it all - Demolitions Expert (retired in China)
- Mz. Ruby, a crocodile - Mystic (jailed)
- Muggshot, a purple, muscular bulldog - Gunman/Enforcer/Brute muscle (jailed)
- Sir Raleigh, a frog in a top hat - Machinist (jailed)
The Fiendish Five was originally formed for the purpose of wiping out the Cooper family. When Sly Cooper was 8 years old, they attacked the Cooper home, killing Sly's parents and stealing the Thievius Raccoonus book. They then split the book into 5 pieces and scattered to the far corners of the globe. Sly, sent to an orphanage, vowed to avenge his family and reclaim the book (which was successful).
Unlike their successors, the Klaww Gang, the Fiendish Five had no unified master plan. Each was only out for their own gain. After their defeat, Clockwerk's parts became part of Sly's next long-running mission, while Panda King and Muggshot would appear several years later, Panda King as part of Sly's gang and Muggshot as a rival fighter pilot in Holland.
Each member had their own main base of operations at a specific location, which is:
- Clockwerk, Krack-Karov Volcano, Russia - Fortress/HQ (destroyed)
- Panda King, Kunlun Mountains, China - Stronghold (abandoned)
- Mz. Ruby, Haitian Jungle/Swamp, Haiti - Voodoo factory (abandoned)
- Muggshot, Mesa City, USA - Casino (closed down)
- Sir Raleigh, Welsh Triangle, Near Scotland and England - Ship (removed)
The Recovery of the Thievius Raccoonus
The Fiendish Five's primary objective seemed to be solely the theft of the Thievius Raccoonus, which Raleigh found himself. After killing Sly's father and dividing the book up into sections (though Clockwerk got the least), Clockwerk chose to leave Sly alive, believing that he'd be no threat without the book. The Fiendish Five went their separate ways, each one with their own schemes in mind.
Raleigh started the legend of the Welsh Triangle by creating a storm device to sink ships that entered his area of influence. Muggshot took over Mesa City, slowly driving out the locals and turning the city into his own personal gambling empire. Mz. Ruby withdrew from civilization entirely, preparing an army of voodoo creatures to unleash terror on the world. Panda King returned to China to take out his aggression on the countryside that spurned him with an avalanche-based extortion racket. And finally, Clockwerk headed to Russia to begin his own plans. Sly, after years of training, began to track each one of them down.
He first confronted Sir Raleigh in his fleet, hidden in the Welsh Triangle; stealing keys throughout his ship to eventually make his way to Raleigh's personal airship, where he confronted the technician and defeated him, leaving him passed out. Raleigh is later arrested and jailed by Carmelita.
Sly then traveled to Mesa City; confronting Muggshot in his own personal penthouse and defeating him, leaving him knocked out. Muggshot is later arrested and jailed by Carmelita, but eventually escapes.
Sly's next goal was in Haiti, where he did everything he could to mess up Mz. Ruby's voodoo plans before defeating her in a rhythmic battle. Carmelita arrested her as well and her voodoo activities earned her a life sentence behind bars.
Sly then confronted Panda King in his personal temple/fireworks factory and defeated him in a martial arts duel. Panda King was also arrested and jailed by Carmelita and released after he served his sentence.
After installing modifications he got from Otto Van Cooper's part of the Thievius Raccoonus to the van, Sly then traveled to Russia, where Clockwerk's high-tech fortress waited. Clockwerk tried to kill Sly multiple times, but in the end, with Carmelita's help, Sly disabled his body by knocking his head off, along with destroying his death ray, ending Clockwerk's threat for the moment.
With the death of Clockwerk and the arresting or retirement of other members, the Fiendish Five collapsed as there were no more members left active.
- While Clockwerk, Panda King, and Muggshot all reappeared in the two sequels at some point (Clockwerk was also in Sly 2: Band of Thieves, and Panda King and Muggshot were in Sly 3: Honor Among Thieves), Sir Raleigh and Mz. Ruby have yet to reappear. Although this could easily be explained by the fact that they simply never escaped jail.
- The Fiendish Five may be a play on to the Fearsome Five, a DC Comics villain group and/or the villain group of the same name from the Darkwing Duck television series.
- Portraits of the Panda King, Muggshot, Mz. Ruby and Sir Raleigh all appeared in the Cairo Museum in Sly 2.
- In the Sly Cooper and the Thievius Raccoonus credits, Mz. Ruby was the only member of the Fiendish Five to be credited in the "Voice Actors" section.