Initially inspired by a United Nations report from the Intergovernmental Panel on Climate Change, they[a] joined Just Stop Oil in August 2022 and were arrested three times in their first week.
An October 2022 protest, in which Plummer and Anna Holland threw tomato soup at a Vincent Van Gogh Sunflowers painting at London's National Gallery, caused worldwide outrage and £10,000 damage to the frame but emboldened activists to carry out similar actions.
In November, Plummer and other activists caused tailbacks on multiple roads in West London with a slow march protest, for which they faced the first jury trial under section 7 of the Public Order Act 2023.
[1] Plummer grew up in Chelsea in London and attended St Mary's School Ascot for three years[6] before obtaining A-levels in Chemistry, Computer Studies, and Maths at Mander Portman Woodward College in Kensington.
[5] Around this time, Just Stop Oil started a campaign of rolling roadblocks and protests, which Plummer signed up for in August[2] after feeling as though they had made all the individual lifestyle changes they could make.
[2] On 14 October 2022, Plummer and Holland entered London's National Gallery, threw Heinz tomato soup at the painting Sunflowers, glued themselves to the wall, and demanded to know whether art was worth more than life, food, and justice.
[2] The protest caused worldwide outrage, though some were assuaged by the fact that the painting was behind glass and was itself unharmed,[6] and the pair received significant queerphobic abuse from social media and right-wing newspapers following the incident.
[4] In an interview with Damian Whitworth of The Times published in July 2024, Plummer stated that they had received "hot food, shelter, clean clothes, [and] warm blankets" in prison, all of which "millions in the global south" had already lost to climate change.
[6] Plummer later posed for Dazed in summer 2023, for which they had 'Stop Oil' written on their chest, held a can of Heinz tomato soup, and wore a silk and cotton sweater by Loro Piana.
[9] In July 2024, Plummer and Holland were convicted by Judge Christopher Hehir of causing criminal damage for their tomato soup protest and warned to expect prison.
Plummer and another activist were arrested five days afterwards for spraying paint at departure boards at Heathrow Airport;[12] a trial in January 2025 resulted in a hung jury and was rescheduled for May 2026.