Doug and Dinsdale Pirhana were leaders of a British criminal gang known as "The Gang". They became entangled by certain means with the League of Extraordinary Gentlemen in 1969.
The Piranha Brothers were born in the slums of London in 1929, on probation, two weeks apart (with Dinsdale born again a week later). They were found too mentally unbalanced even for National Service, and became extortionists, running a protection racket after several false starts. Having acquired enough money, the Piranha Brothers formed a gang which they called "The Gang". They proceeded to take over night clubs, billiard halls, gaming casinos and race tracks, failing only to acquire the MCC. It is said that Dinsdale was a gentleman; he bought his mother flowers and that he knew how to treat a female impersonator. Despite a jaw-dropping violent streak — including nailing people's heads to the floor and to coffee tables, and screwing people's pelvises to cake stands — he was beloved by everyone who knew him, most considering him "a cruel man, but fair". The local chief constable was in his employ, and would help him threaten others with a thermonuclear device. Dinsdale also possessed a tank. Known associates of the Piranhas included American musical stars, aristocrats, a man named Kierkegaard who bit the heads off whippets and other gang leaders.
Doug, on the other hand, was the most feared man in the London underworld. Luigi Vercotti, a pimp, claims to have seen grown men pull their own heads off rather than speak to Doug – indeed, even Dinsdale feared Doug. This was largely due to his merciless use of sarcasm, dramatic irony, metaphor, bathos, puns, parody, litotes and satire. Many of those menaced by the Piranha Brothers denied any ill will toward them, terrified into compliance with a code of silence.
Dinsdale was deeply afraid of Spiny Norman, an (apparently) imaginary hedgehog who, he believed, lived in a hangar at Luton Airport and who "was wont to be about twelve feet from "snout to tail", (one version states "about twelve feet from "tip of his snout to his anus"); when Dinsdale was depressed, Norman could be anything up to eight hundred yards long." Spiny Norman (created by animator Terry Gilliam) appeared in this sketch growling "Dinsdale!" while towering over London landmarks such as Buckingham Palace and Trafalgar Square; the giant hedgehog made brief reappearances in two later episodes.
The Piranhas operated their extortion racket for years, brazenly and without fear of reprisal. However, Dinsdale's fear of Spiny Norman proved to be their undoing, as he decided to solve the problem once and for all by detonating his nuclear device at Luton Airport in February 1966. After this, even the Police sat up and took notice of them.
The brothers were finally captured by Superintendent Harry 'Snapper' Organs (played by Terry Jones) of Q Division, who pursued them in a series of disguises including Blind Pew from Treasure Island, the Earl of Gloucester from King Lear, Sancho Panza from Man of La Mancha, and Ratty from Toad of Toad Hall. However, the Piranha Brothers later escaped, and presumably returned to their life of absurd crime.