A presenter (John Cleese) introduces the topic of the violence of British gangland. He announces that the notorious Piranha Brothers, Doug and Dinsdale, were sentenced to 400 years of imprisonment. The programme will show the viewers how the Piranhas rose to power, how they subjugated rival gangs and how they were captured by superintendent Harry "Snapper" Organs.
The Piranha Brothers
The presenter narrates the early life of the brothers: Doug was born in February 1929, and Dinsdale 2 weeks later, and again one week later, born on probation, the eldest sons in a family of 16. Their father was Arthur Piranha, a scrap-metal dealer and TV quizmaster, who married their mother, Kitty Malone, an up-and-coming East End boxer.
Mrs April Simnel (Michael Palin) is interviewed (by Eric Idle) and describes the violence of Kipling Road, the street where the brothers grew up in. (A line of gas men from the New Cooker Sketch are still there.) She says Doug was keen on boxing and how much he liked to put his boot in people's groins.
The scene then cuts to Ernest Pythagoras Primary School, where the brothers' former English teacher Anthony Viney (Graham Chapman) is interviewed (by Terry Jones), however, the interviewer points the microphone to himself when Viney is talking, and to Viney when he is talking, so none of them can be heard. Viney explains an implied violent story with gestures.
The Brothers were deemed too mentally unstable by the Army Board, and even the National Service. Instead, they would perform "The Operation", where they would threaten to beat up a victim if he paid them the "protection money". Then they started another operation called "The Other Operation", where they threatened not to beat up a victim if he didn't pay them. One month later, they began "The Other, Other Operation", where the victim was threatened that if he didn't pay them up, they would beat him up. The presenter makes special note that this change marked the “turning point” for the brothers. Superintendent Harry "Snapper" Organs (Jones) explains how the brothers formed a gang called "The Gang". He also describes how he and the rest of Q-division kept tabs on their gang's every move by reading the “colour supplements” in the daily newspaper.
Vince Snetterton-Lewis (Chapman) explains how he was chained to the back of the brothers' tank and how Dinsdale split his nostrils open, sawed his legs off, and pulled his liver out, and finally nailed his head to the floor.
The interviewer asks Stig O'Tracey (Idle) about how Dinsdale nailed his head to the floor, to which O'Tracey denies it and expresses his friendship with Dinsdale, even though the police have film of it. He then agrees it happens and tells the interviewer how it was his fault it happened, even though Dinsdale never gave him the reason why. The interviewer then reveals he nailed O'Tracey's wife's (Chapman) head to the coffee table, who denies it even though there is a huge coffee table nailed to the top of her head. Mr O'Tracey says "he was a cruel man, but fair."
Vince says how he went to Dinsdale's every Sunday to apologise, and he'd nail his head to the floor. However, on one occasion when he was going to meet his parents, Dinsdale agreed to only screw his pelvis to a cake stand. A man (Jones) with a lamp sticking through his head and a table through his chest tells the audience "He was the only friend I ever had". Another man who has his head stuck in a block of concrete says "I wouldn't hear a word against him.", and a man in a grave with the words "RIP & good luck to Dinsdale" says he was a lovely fella.
The presenter asks what he was really like, and it cuts to Gloria (Cleese) who describes how Dinsdale was a charming, cultured man, but explains how he believed he was being watched by a giant hedgehog called "Spiny Norman", 12 feet long, but 800 yards long when he was very depressed. She describes how Dinsdale acted weirdly when Norman was present.
A Criminologist (Chapman) expresses his understanding towards Dinsdale's actions. Luigi Vercotti (Palin) is interviewed whilst sitting in an escort agency office but has to serve a customer over the phone discreetly, and carries on describing his conflict with the brothers. He describes his traumatising encounter with Doug Piranha, who terrified everyone by using sarcasm.
Gloria explains how Dinsdale became increasingly frightened by Spiny Norman and how he had blown up Luton Airport as he believed Norman lived here. The Superintendent describes how he tracked down the Piranha Brothers, following in various disguises, including being involved with a panned performance as Sancho Panza. It cuts to the Superintendent and another constable, Hawkins (Chapman) applying makeup in a dressing room ready to go on stage. The Silly Walks Ministry worker walks past them as they exit the building.
The show ends with a newspaper man calling "Piranha Brothers escape!", finally scattering the long line of gas men in fear. As the credits roll, the voice of Spiny Norman (Terry Gilliam) is heard calling "Dinsdale?", and can be seen popping up in various parts of London looking for Dinsdale.