The football event of the Rio Olympics 2016 may have already kicked off, but the real deal starts in earnest on Friday when the opening ceremony takes place at the iconic Maracana Stadium. The most eagerly anticipated event of any sporting extravaganza, the opening ceremony is expected to draw a television audience of three billion people worldwide.

Although the details of the opening ceremony have been kept quite close to the chest, organisers have been revealing glimpses of a few key attractions as teasers regarding who will perform in the opening ceremony, which gets underway at 5:00am Saturday Bangladesh time. The ceremony will be dominated by Brazilian music and dance, with two of the South American nation's famous singers -- Gilberto Gil and Caetano Veloso -- handpicked to enchant the audience.

Brazilian supermodel Gisele Bundchen, who made an appearance at the prize giving ceremony of the FIFA World Cup at the same venue two years ago, will play the part of the famous 'girl from Ipanema'. The 35-year-old Victoria's Secret model is expected to be accompanied by 6,000 dancers from 12 Samba schools who will celebrate 'the evolution of the people of Brazil'. This section of the show will include tributes to the rainforest and will capture the spirit of the Rio Carnival, a festival held before Lent every year and considered the biggest carnival in the world.

The samba will be followed by the athletes' parade, when 12,000 athletes and delegation members of 206 nations will walk through the athletics track, which will be the longest part of the show.

The most eagerly anticipated part of the show, the lighting of the Olympic Cauldron, has been kept a secret like always even though football legend Pele is highly tipped to perform this act.

The whole event, which will be more than three hours long, has been designed and orchestrated by three creative directors. Acclaimed movie director Fernando Meirelles being the head of the creative team. Meirelles, the director of Oscar-nominated 'City of God', said that while there will be no shortage of Brazilian culture and its exotic elements showcased during the show, budget constraints have meant the razzmatazz will be low-key compared to London 2012 and Beijing 2008.

"We were looking at a budget of 113.9 million US dollars for the four ceremonies -- opening and closing ceremonies for the Olympic and Paralympic Games. But now our budget is 55.9 million US dollars for four ceremonies. Most of this money is for security, and all the stuff around the show. I think it is 12 times less than London, 20 times less than Beijing. This makes it very challenging," Meirelles said in a statement released by the local organising committee.

"I have never done anything on this scale, and will never do so again in my life," he added. "Everything is very big, the stage is very big. It's a huge responsibility."