Duke Dexter is a famous, and not very bright, pop singer.
Dexter was featured on national television singing one of his hit songs (in front of a set that looked very similar the one used by the band The Doors on the Ed Sullivan show). He also performed at a show in Denver, Colorado, where Phones claimed his niece had managed to get a piece of his jacket.
Dexter performed a series of concerts as part of a recruitment drive for WASP, and one of his concerts had him appear at Marineville. Before performing, he was kidnapped by Titan who then mistook him for a master mind controller of the Terran population, and set him free to continue his master work. A clueless Dexter then returned to Marineville and performed a concert later that night.
His most well known song was one he performed at Marineville, and was featured on national television.