Plastics have become an essential material of the modern global consumer economy, yet many of the properties that make them useful in so many applications also make them a serious environmental threat. As for much new technology, their development and proliferation occurred with little consideration for their impacts, but now it is impossible to deny their dark side as we confront a rapidly growing plastic pollution problem. In this special issue, we examine a range of topics related to plastics, from their distribution in the environment to their development into an evolutionary trap for animals to ways we can rethink them to create a better future. A series of Reviews discusses how plastics are best understood as novel geomaterials, the evolutionary and ecological dimensions of plastic ingestion by wildlife, the accumulation and effects of plastic pollution in the environment, and how innovations in upcycling and recycling may affect the fate of plastics and drive advances in next-generation materials design. Complementing these Reviews, a Policy Forum and a pair of Perspectives discuss efforts to develop a global agreement to combat plastic pollution, provide an overview of the history of environmental bioplastics and their implications, and offer suggestions for designing plastics for a circular bioeconomy. Finally, a brace of News Features explores how enzymes are being used to aid in plastic recycling efforts and how museums are trying to stop plastics in their exhibits from breaking down. The time for preventing plastic pollution is long past—the time for changing the future of plastics in our world, however, is now. ![Figure][1] Impacts of plastic waste on marine speciesPHOTO: NASTCO/ISTOCKPHOTO; GRAPHIC: K. FRANKLIN/ SCIENCE ; DATA SOURCE: [HTTPS://OURWORLDINDATA.ORG/PLASTIC-POLLUTION][2]; GEYER ET AL., SCI. ADV. 3 , E1700782 (2017); JAMBECK ET AL., SCIENCE 347 , 768 (2015) [1]: pending:yes [2]: https://OURWORLDINDATA.ORG/PLASTIC-POLLUTION