Brazil's power companies are braced for another surge in demand on Friday night as millions follow the latest twists in a soap opera that has gripped the nation.
Avenida Brasil has become such an unprecedented phenomenon that even President Dilma Rousseff felt obliged to change her work plans for the evening.
Brazilians are known to take their soap operas or novelas seriously, but this one has even surpassed another national passion, exceeding audiences for a recent football final.
As well as being a compelling watch, the show is notable for putting Brazil's growing middle class centre stage where in the past it was the lives of the super wealthy which dominated.
Faced with such competition for attention, it was no surprise President Rousseff cancelled plans to attend an important local election rally in Sao Paulo, fearing the turn-out would be a fiasco.
Who killed Max?
With episodes of Avenida Brasil attracting 50% of the viewing public, common political sense dictated it would be better to address the party faithful on another occasion.
For the climax, restaurants and bars are holding events in many cities and bets are being placed to find out the plot's final mystery: "Who killed Max?"
Avenida Brasil employs the usual high levels of melodrama, combined with an intricate story based on a little girl who comes back as an adult to avenge the death of her father.
Viewers have been gripped by the battle between Rita and a now legendary villain, Carminha, the evil stepmother who abandoned her in a landfill site as a child.
Meanwhile Brazil's so-called "new middle class" is relishing its place in the spotlight in Avenida Brasil.
The typically rich, aristocratic protagonists of the Brazilian novelas, often with living standards which 99% of the public can only dream of, have been put to one side.
Instead they made way for loud, adorably unrefined suburban characters in the leading roles - and the minor parts as well.
It was seen as a shrewd move by Rede Globo - the TV channel that dominates the Brazilian soap opera industry - shifting onto territory closer to its biggest audience.
With the growth of the Brazilian economy and wider availability of credit and government cash transfer programmes, 35 million people have in recent years joined an expanded middle class.
Today it not only accounts for more than half of the Brazilian population but has also become the country's largest and most coveted consumer market.
According to research institute Data Popular, this group owns half of Brazil's credit cards and has spent one trillion Brazilian reais ($US490bn; £300bn) last year alone.
Avenida Brasil has succeeded in attracting this section of the population, triggering a wave of consumption that advertisers dream about.
The scantily-dressed character of Suelen has had women flocking to popular shops seeking versions of her earrings and clothes.
The hair salon owned by Monalisa launched, within the soap opera, a hair product made to be sold in real life. It is now available in shops with the character's name.
The novela is so successful because lots of effort was put into understanding the behaviour of the new middle class, their clothes, values and aspirations, says the Director of Data Popular, Renato Meirelles.
"It reflects a middle class that wants to see itself portrayed. It's different to the nouveau riche portrayed in the past, who wanted to hide their origins," he says.
"These characters are proud of their origins," says Meirelles, citing the character of Tufao, a successful football player from the suburbs who sticks to his neighbourhood when he became rich.
The story is set in an imaginary district in the suburbs called Divino, where everyone knows each other, hangs out at the local bar and gossips about their neighbour's latest indiscretions.
It is a long way - both culturally and geographically - from the southern zone of Rio, where the beaches and richer neighbourhoods are well known to tourists.
Instead the show reflects the reality of the north of the city, an area crossed by Avenida Brasil, the main highway that leads from the outskirts of the city and across the suburbs into central Rio.
When the hairdresser of the novela decides to try out the south zone and live in exclusive Ipanema, she complains that the men are too fussy and the neighbours don't know each other.
Before long she has headed back to her comfort zone.
"When we portrayed poor people, they were always dreaming of leaving their suburbs and striking it rich," Ricardo Waddington, co-ordinator of Avenida Brasil, told the daily newspaper Folha de São Paulo.
"But now we want to show a place that, in spite of being poor, is cheerful and warm, a place where there can be prosperity."
Mr Meirelles says Brazil's elite has had two different reactions. On the one hand, a more traditional group sees it as story-telling and finds it funny.
But among the wealthy are also people with humble origins, and they enjoy it the most, he believes.
"Over 40% of people in the upper classes are actually the first generation of people with money in the family.
"People who grew rich through their own sweat and therefore have an A-class pocket but a C-class taste. So they see themselves in the novela and delight in it."
Globo TV appears so pleased with the outcome it seems to want to extend the formula.
Its next novela will be set in a shanty town or favela which was recently occupied by police as part of a "pacification" programme in advance of the World Cup and Olympics.