High Quality Content by WIKIPEDIA articles! Robert Dunham (July 6, 1931 - August 6, 2001) was an American actor, entrepreneur, writer, racecar driver, and a US Marine. He is probably best known for his role as Antonio, Emperor of Seatopia in Godzilla vs. Megalon (1973); Dunham`s biggest role would be that of Mark Jackson in the Japanese film, Dogora (1964) and Captain Martin in The Green Slime. Dunham was an American living in Japan during most of the country`s "Golden Age" of cinema, and worked in films directed by Ishiro Honda, Jun Fukuda, and Kinji Fukasaku. He sometimes was billed as Dan Yuma or Danny Yuma.