Despite being chock-full of hardcore science, 3 Body Problem, a television series released on 21 March by the streaming service Netflix, has been a hit with audiences. The story follows five young scientists who studied together at the University of Oxford, UK, as they grapple with mysterious deaths, particle-physics gone awry, and aliens called the San-Ti who have their sights set on Earth. But how much of the science in the sci-fi epic reflects reality, and how much is wishful thinking? To find out, Nature spoke to three real-world scientists, including School of Chemistry & Biochemistry professor Younan Xia.