After returning to Europe by sailboat, Greta Thunberg greeted the throngs of press and young climate activists who trail her everywhere. She rested for a day, then returned to the sea to be photographed for TIME’s Person of the Year cover.

The image was taken by Evgenia Arbugaeva, who grew up in the Russian Arctic, and makes photos of remote, quiet and unlikely beauty. “When TIME asked me to photograph Greta, I was thinking how can I make a portrait that combines gentleness and at the same time courage. How do I capture the intense, focused gaze inwards as well as outwards, which I feel is characteristic of Greta,” she says. “It was not an easy task.”

Arbugaeva wanted a photograph that captured the spirit of the young activist. She started by creating a mood board with references from Botticelli, Monet, Norse mythology, tarot cards, and Romantic period art.

Photographer Evgenia Arbugaeva, who grew up in the Russian Arctic, scouted Lisbon for two days before choosing a rocky beach near the city as the setting for the TIME cover shoot on Dec. 4. Suyin Haynes

She arrived in Portugal while Thunberg was still at sea and began scouting greater Lisbon for a location. “One day I saw a quiet winter beach with almost no people besides some fishermen,” Arbugaeva says. “I had to consider privacy because the crowd surrounds Greta everywhere she goes. “I thought it was perfect.”

Climate activist Greta Thunberg photographed on the shore in Lisbon, Portugal December 4, 2019 Photograph by Evgenia Arbugaeva for TIME

The photo shoot would come in the thick of TIME’s reporting. Before setting off from Hampton, Va., three weeks earlier, Thunberg was interviewed by national correspondent Charlotte Alter and climate correspondent Justin Worland aboard the catamaran La Vagabonde. In Lisbon, the teen met up with London-based correspondent Suyin Haynes, who had spent five days with Thunberg in April—at home, school, and on a 1,200 mile train journey—for an earlier profile published as part of TIME’s May 27, 2019, “Next Generation Leaders” issue.

Thunberg arrived at the beach in a Tesla rented to bring her to the shoot. The sun was going down. “As she stood for a photograph, the sky colored golden pink creating beautiful light, ocean tide was rising and waves were raging around her,” Evgenia recalls. “Greta stood tall and strong without moving, just a few strands of her hair fluttering in a gentle breeze. She looked straight ahead into the ocean she just crossed. At this moment it felt as if all nature elements and forces aligned to create the magic—the most treasured gift for a photographer.”

It may have been the last moment of peace the activist would have on the trip. The next day, she boarded a night train to Madrid, accompanied by Arbugaeva, Haynes and the media horde that would track her every step in the Spanish capital, where tens of thousands demonstrated outside the U.N. climate conference.

“From then on, crowds of journalists and security guards are constantly around Greta,” says Arbugaeva, who graduated from the International Center of Photography in New York in 2009. “It was the first time I saw something like this, a real insane hysteria of people trying to get to her…But Greta seemed to handle it very well. I could see that she is on her mission.”

This article is part of TIME’s 2019 Person of the Year package. Read more from the issue and sign up for the Inside TIME newsletter to be the first to see our cover every week.

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