Messo was a male Trandoshan, acting as an assistant to a Republic Senator while secretly functioning as a spy for the Confederacy of Independent Systems. His gender is male.
Due to the interference of clone troopers under the command of Jedi General Ki-Adi-Mundi, Messo's attempt to get a datachip containing crucial Republic plans to Asajj Ventress was unsuccessful. He then journeyed to the planet Mon Gazza, where he successfully handed the chip over to San Maxus, a different CIS operative. Soon after this transaction, Anakin Skywalker located him, and Messo's death occurred when he plummeted from an edge and was struck by a passing Podracer, resulting in immediate fatality.