NASA’s Cassini spacecraft arrived at Saturn in 2004, beginning an epic thirteen-year tour of the ringed planet and its many moons. Cassini carried an impressive array of scientific instruments, including the Composite Infrared Spectrometer (CIRS) built at Goddard Space Flight Center. By studying the Saturn system in heat radiation, CIRS observed hot spots in a giant Saturn storm, discovered a new hydrocarbon in Titan’s smoggy atmosphere, found unexpected surface heating on Mimas and Tethys, and even detected evidence of a liquid water ocean under the icy shell of Enceladus. Join instrument team members Micheal Flasar, Conor Nixon, and Carrie Anderson as they retell Cassini CIRS’ greatest hits. This director’s cut version features an extended introduction and conclusion.