Alex Robinson gets into the carnival spirit

I am lost in a sea of bodies that moves like a wave down the street, rippling to the pounding cacuria beat. They swirl, in brilliantly coloured rainbow dresses, and smile – myriad Brazilian faces of all colours and shapes. There are black girls with green eyes, Indians with Asian features under manes of tawny dyed hair. The night is warm and sweaty under a cloak of sparkling stars. Street lights illuminate both the blue and white azulejo tiles on the 18th-century buildings and the bell tower of a Portuguese church.

We are gathered for one of Latin America's biggest parties – an annual revel that draws thousands to the city of Sao Luis from the backlands of the Brazilian North East. The festival focuses on one of the world's most vibrant and unusual pageants – the Bumba Meu Boi – which tells the story of two Brazilian peasants who steal, slaughter and eat a prize bull that belongs to a rich Portuguese landowner. The furious owner threatens to kill the couple but they resurrect his bull, with the help of a Catholic priest, an African-Brazilian witch doctor and an indigenous shaman, and after their triumph they hold a huge party.

The party has already started here in Sao Luis's streets. But the pageant hasn't begun. We reach a handsome city square, dominated by a vast stage. The drums stop and hundreds of dancers file on to the stage. They are dressed as Indians, in feather headdresses, or as hobby horses, or grotesque clowns in grinning masks. Another rhythm pounds and they move in perfect unison. A pantomime black bull, covered in rainbow patterns, bucks and frolics between them. The crowd roars, leaps, gyrates. The energy is overwhelming.

I spend the next three days at the festival relaxing under the palms on Sao Luis's sweeping white sand beaches during the day, eating fresh rock lobster for lunch – washed down with revitalising acai juice – then partying at night. It's an extraordinary time – and I feel all the more privileged because it feels like a secret world. For while there are millions in Sao Luis enjoying Bumba Meu Boi, I am, it seems, the only foreigner.

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