Lagos is in full festive mode as the first Harmattan winds usher in “Detty December,” the annual holiday season when Nigerians at home and in the diaspora flood the city for celebration, concerts and nightlife. From sprawling festivals to packed nightclubs, Africa’s most populous city transforms into a playground of excess and energy.

As dusk fell around 6 p.m., early revellers gathered at the Detty December Festival near Ilubirin, a half-finished housing estate reclaimed from the Lagos Lagoon. Technicians fine-tuned lighting and sound systems while guests trickled in for weeks of performances. For many, the season offers a release after a demanding year. “After the whole hustle and bustle, Detty December is the time to enjoy myself and just let loose,” said Chioma Chinweze, a marketing consultant attending the event.

By 8 p.m., acrobats performed beneath a moon hoisted by a crane as the crowd thickened. Visitors from across Nigeria and the diaspora mingled, with some hotel operators noting an increase in foreign tourists. “This one’s going to be bigger than last year,” said Taiwo Akintunji, a nurse visiting from Los Angeles.

The night intensified by 11:30 p.m. on Victoria Island, where upscale lounges buzzed with activity. At Mr. Panther, a rooftop club, champagne flowed freely as music pulsed through the crowd. Club manager Charbel Abi Habib said December is the most lucrative period for nightlife businesses. “To be honest, the money is made during Detty December,” he said. For partygoers, the season offers a brief escape from economic pressures. “December is where you are just carefree,” said makeup artist Michelle Wobo.

Despite Nigeria’s ongoing economic hardship and security challenges, the party showed no signs of slowing by 2 a.m. Guests moved seamlessly from one venue to another, including newly opened clubs. “I feel the safest I’ve ever been,” said Liberty Mini, an interior decorator who has lived in Lagos for three years.

At around 4 a.m., the energy peaked at another Victoria Island nightclub where Afrobeats star Tiwa Savage made a surprise appearance. Music, dancing and swirling smoke filled the room as revellers celebrated into the early hours.

By 5 a.m., some guests began stepping outside for air, surrounded by luxury cars lining the car parks. Real estate agent Babatunde Olabode said he planned to rest briefly before returning to the festivities. “Party continues tomorrow,” he said.

As Detty December rolls on, Lagos once again reaffirms its reputation as a city that, for a few weeks each year, parties without pause.