Contenders ranging from Russian grannies to a Swedish disco starlet are facing off in the Eurovision song contest for a glitzy spectacle which host Azerbaijan hopes will banish qualms about its questionable rights record.
Saturday's Eurovision extravaganza is the biggest event ever hosted by energy-rich Azerbaijan as it seeks to present a glossy front to the world despite the intolerance of dissent and opposition under the rule of the Aliyev dynasty.
The final round of the song contest, featuring entries from 26 countries, began airing live from the Crystal Hall on the city's Caspian Sea bay from midnight local time (1900GMT) to an audience of an estimated 125 million television viewers.
Going into the final, the favourite to win is Sweden's entry, Loreen, a 28-year-old singer who performs an upbeat number called "Euphoria" with high-kicking dance moves and a fake snowstorm.
Also hotly fancied are Russia's Buranovskiye Babushki, a choir of elderly women from a single village in the Ural Mountains who perform a song set to a disco beat called "Party for Everybody", with most of the lyrics in their native Udmurt language.
Equalling the eldest of the babushki in age at 76 is Britain's entry, veteran crooner Englebert Humperdinck, with a ballad called "Love Will Set You Free".
The competition got underway with a spectacular display of Azeri folk dancing and a performance by last year's winners Ell and Nikki, whose surprise victory brought the event to Azerbaijan.
The excitement had been building in the capital where electronic billboards were counting down the hours to the final, and the event's logo swirled on buses and a fleet of new London-style black cabs.
"It's fantastic that it's happening in Azerbaijan, in our country," enthused Yunis, 20, a metallurgy student.
But the festive atmosphere was clouded by the arrest late on Friday of dozens of opposition activists who attempted to hold a peaceful demonstration calling for fair elections and respect for civil liberties in the tightly-controlled state.
The Public Chamber opposition alliance said in a statement on Facebook that "more than 60 protesters were detained" and "about 10 protesters were injured", as police, many in plainclothes, bundled them into vans and buses.
A court sentenced three protesters to jail terms of five or six days, while 16 were ordered to pay fines or given warnings, and the rest were released, the alliance said.
Human Rights Watch in a statement released Saturday called for Azerbaijan to respect freedom of assembly, saying it was crushing peaceful protest.
"The authorities should immediately release people picked up at peaceful protests and stop detaining people arbitrarily for legitimate speech," senior researcher Giorgi Gogia said.
Azerbaijan is run by strongman President Ilham Aliyev, who succeeded his late father Heydar Aliyev in 2003.
The president is closely involved in hosting Eurovision and was set to attend the final, with police warning that access to the event would close three hours before the start for his motorcade.
His wife Mehriban Aliyeva heads the organising committee and his son-in-law, Emin Agalarov, a Moscow-based businessman who sings as a hobby, is performing in the interval of the final.
Radio Liberty reported this month that a construction company in the project to build the Crystal Hall venue in a city-commissioned project had links to the Aliyev family.
The event is also far beyond the reach of ordinary Azerbaijanis, with tickets for the final starting at 160 manat ($204).
Rights activists have met Loreen of Sweden, but she declined to comment on her views on human rights when questioned after the second semi-final on Thursday.
The state broadcaster apparently deliberately translated the journalist's question incorrectly, saying she asked Loreen how she felt on stage, local opposition media reported.
One of the activists to meet Loreen was Rasul Jafarov, who is co-ordinating a Sing for Democracy campaign during Eurovision.
Jafarov told AFP he felt she had been intimidated but still hoped she would speak out.
"I think she was under pressure - pressure from our government and from the European Broadcasting Union," he said, referring to Eurovision's organiser.