"Project Hail Mary" is a science fiction novel by Andy Weir, known for his previous work, The Martian. The story follows Ryland Grace, an astronaut who wakes up alone on a spaceship, with no memory of his mission. He discovers that he is on a critical mission to save Earth from an extinction-level threat caused by a microorganism that is consuming the Sun's energy. As Grace navigates his challenges, he encounters an alien named Rocky from a distant star system. Together, they work to understand the problem and develop a solution, highlighting themes of cooperation, ingenuity, and survival in the face of overwhelming odds.