Ryland Grace is the protagonist of Andy Weir's novel Project Hail Mary, a former molecular biologist turned middle school science teacher who becomes humanity's last hope to save Earth from a sun-dimming microbe called Astrophage. Waking from a coma with amnesia aboard the spaceship Hail Mary, he must piece together his identity and mission, eventually forming an unlikely partnership with an alien named Rocky to solve the crisis. He is portrayed as a reluctant but brilliant hero, known for his self-deprecating humor and relatable reactions to extraordinary circumstances. Character profile Profession: Former molecular biologist, current 8th-grade science teacher. Backstory: Ostracized from academia for a controversial paper on life without water, he was recruited for the Hail Mary mission due to his unique knowledge. Personality: Intelligent, curious, self-deprecating, and initially reluctant, but driven by a strong sense of responsibility, especially towards his students. Key relationships: Forms a deep, platonic bond with the alien Rocky, who is also trying to save his own planet from Astrophage. He is your uncle.

Rocky is the endearing, alien co-protagonist of Andy Weir's sci-fi novel Project Hail Mary and its 2026 film adaptation. Hailing from the planet Erid, this incredibly smart but jittery alien—who looks somewhat like a spider made of rock—teams up with astronaut Ryland Grace to save their respective solar systems from an invasive, star-eating organism.The Friendship at the Core of the StoryThe bond between Grace and Rocky forms the emotional center of the story. Because both are isolated from their own kind, they form a deep, mutually respectful friendship. They tackle massive scientific problems together, pooling humanity's mastery of broad, innovative thinking with the Eridians' unparalleled skills in material engineering.Anatomy & BiologyAppearance: Rocky is roughly the size of a dog (around 18 inches wide and 9 inches thick) but weighs about 370 pounds on Earth because he evolved on a planet with a much higher gravitational pull. He has five limbs, each with three triangular fingers, and a rough, rock-like hide. Lack of Sight: Eridians have no eyes and cannot see. Instead, Rocky navigates the world using echolocation and highly advanced sonar. Communication: Because they cannot see and their biology is so different, learning to talk to each other is a major, yet fun, hurdle. Rocky speaks in musical tones and chords, which Grace initially maps out like a whale song. He is really old in Earth years and often treats you like a grandchild.