The photo project was done for the organization Fishlove and included some other U.K.-based celebrities posing in the buff with critters ranging from bass fish to sharks. Its goal is to raise awareness of how overfishing is destroying the oceans. The release of Gillian's nearly nude pic, which was snapped by French portrait photographer Denis Rouvre, is timed with a European Parliament vote on banning destructive forms of deep-sea fishing in the Northeast Atlantic. The Fishlove organization is trying to rally voters to sign a petition ending deep-sea trawling – which, according to scientists, is negatively impacting the fish population and their habits – and Gillian solicited signatures in a Twitter post. Photo: “Fish Love” Project by Photographer Denis Rouvre. Gillian Anderson. (Photo by Denis Rouvre)

Moscow riot police prepare to move on activists during an unsacnctioned anti-Putin opposition rally at the Pushkin Square March 5, 2012 in central Moscow, Russia. Amid charges of fraud, demonstrators took to the streets a day after Vladimir Putin declared victory in Russia's presidential elections. (Photos by: Rustem Adagamov; Source: LiveJournal; Gleb Shchelkunov; Source: LiveJournal; Ilya Varlamov; Source: LiveJournal; Raskalov; Source: LiveJournal; Dmitry Chistoprudov; Source: LiveJournal)

Tourist Amy Powers is approached by “Walker” Matthew Tomlin during The Walking Dead Tour of a Season 3 location of the AMC production in Haralson, Georgia, U.S. on June 15, 2019. (Photo by Chris Aluka Berry/Reuters)

TVs display a reaction of Japan's Uta Abe, the gold medallist of the judo women's -52kg during the Tokyo 2020 Olympic Games, to celebrate the victory of her brother Hifumi Abe as he wins the judo men's -66kg final at an electronics retail shop in Tokyo on July 25, 2021. (Photo by Yasuyoshi Chiba/AFP Photo)

Marcus Semien #2 of the Texas Rangers is doused with sports drink after the game against the Seattle Mariners at Globe Life Field on June 03, 2023 in Arlington, Texas. (Photo by Sam Hodde/Getty Images)

Model friends Bella Hadid, Kendall Jenner, Stella Maxwell and actress Kristen Stewart and are seen having dinner together in Milan, Italy on June 16, 2018. Bella and Kendall cheekily showed the camera middle finger while couple Stella and Kristen talked. (Photo by Splash News and Pictures)

Masked dancers perform a ritualistic dance at Kathmandu Durbar Square during the procession of erecting a sacred pole locally called “Ya: Shi”, marking the formal start of Indra Jatra dedicated to rain god Indra in Kathmandu, Nepal, on September 15, 2024. (Photo by Subaas Shrestha/NurPhoto/Rex Features/Shutterstock)

People wait for a subway train to depart Union Square station, in New York City on June 1, 2025. (Photo by Kevin Coombs/Reuters)