The name of Matt Damon’s character in Christopher Nolan’s Interstellar is Dr. Mann.
Dr. Mann is an astronaut and scientist sent to an icy world as part of the Lazarus missions, an earlier effort to find habitable planets for humanity. He is discovered in cryogenic sleep by Cooper’s Endurance crew after they follow the signal from his planet.
Mann initially claims that the planet can support colonization, but the film reveals that he falsified his data because he feared dying alone and wanted a rescue mission to arrive. His desperation makes him one of the film’s central antagonists, even though he began as a celebrated explorer.
Viewers sometimes confuse Damon’s role with Cooper, played by Matthew McConaughey, or with Romilly, played by David Gyasi. Dr. Brand is another major character, portrayed by Anne Hathaway; she is not Damon’s character. Damon’s brief appearance was also easy to miss because the film’s marketing kept it largely secret.