Behind the flamboyant costumes and deafening drumbeats lurks a murky world. Many of the samba schools are controlled by mafia-style bosses. In the past nine years, 14 people linked to samba have been murdered in Rio; not a single case has been solved.
Preparations for Rio de Janeiro’s dazzling carnival have been tainted by the murder of one of its organisers over his choice of parade queen.
Now, the dazzling pink and green colours of Rio’s most traditional and beloved samba school, Mangueira, have been spattered with blood. Robson Roque, the 43-year-old president of the percussion section, appears to have been shot, decapitated and then burned.
Police discovered what are believed to be his remains in a makeshift crematorium or "microwave" made of tyres at the top of the Mangueira favela.
Rio has long been defined by samba. For five days each February, the city virtually shuts down for the mega-industry that is Carnival.
According to government figures, Carnival generates £200m annually. Last year, 380,000 tourists flocked to the event – many of them parading in the verde e rosa (green and pink) strip of Mangueira.
Mr Roque’s case is mired in confusion. "None of us in the samba world know what the motive was, but it’s normally about personal disputes," said Noca da Portela, a composer of 52 years who knew him well.
"Apart from being a father and a great friend, he was a beloved member of the Mangueira community," he said.
Police believe the murder was triggered by a row over a woman. Each year, Rio’s samba schools each elect a rainha (queen) to parade in front of their musicians. Along with the huge drumming troupes, the rainha is the defining image of Carnival, flaunting her half-naked, sequinned body as the groups parade through Rio’s purpose-build samba stadium, the Sambódromo.
But as in many of Rio’s shanty towns, or favelas, it is cocaine that talks in Mangueira, controlled by the Comando Vermelho drugs faction. Local traffickers are thought to have objected to this year’s choice of queen and to have responded by murdering Mr Roque and burning his body in a manner normally reserved for investigative journalists and police informers.
Police are apparently also investigating rumours that Mr Roque may have had an affair with the wife of Mangueira’s drug lord – Francisco Paulo Testa Monteiro (or Tuchinha), who is currently in prison for drug trafficking. Brazilian newspapers have speculated he was also involved in other gangland operations.
But Mangueira’s president Alvaro Luiz Caetano denied traffickers were involved. "This possibility does not exist. Everybody was happy with the election," he said. Other sources told The Independent it was usual for samba schools to remain neutral in such situations, presumably so as not to further offend the drug traffickers.
Mangueira is Rio’s third oldest favela, and now houses 14,000 impoverished Brazilians. Perched on a hilltop in the city’s north zone, its redbrick shacks form a crucial chapter in samba’s history. Hundreds of songs pay tribute to its magnificent views. "From high up here, it looks more like a heaven on earth," samba-star Elizeth Cardoso sung in 1970.
Yet since the cocaine trade hit Rio in the early 1980s, Mangueira has been ravaged by violence. Soldados (foot soldiers) patrol its cramped alleys with rifles and machine guns. Last year the American actor Dennis Haysbert cancelled a trip there for security reasons.
Mangueira residents now fear the murder could scare visitors away, but Rio’s samba community are playing down Mr Roque’s death. "Mangueira is one of the safest samba schools in Rio," insisted Mr da Portela. "You won’t see a fight there in a million years."
But the composer accepts the city is facing a huge problem with violence. This year his school will compete against Mangueira in the Group A final with a samba called: "We Can: Eight ideas to change the world", which urges Brazilians to combat violence.
Officials at Mangueira’s HQ are remaining tight-lipped about the murder. "Everything here’s peaceful," said one employee, who refused to be named. "The community’s upset but we’re going to carry on as normal."