Okasa is a Japanese male and ninja warrior who was a recurring villain on the show The Master. Trained by John Peter McAllister - an American who became the first western ninja master - he was greatly angered when McAllister decided to renounce his ninja ways and return home to search for his daughter.
Okasa followed McAllister to the United States, and tailed McAllister and his new American student Max Keller. Several times he engaged McAllister in combat. In their first duel in the United States the pair fought in a computer room, and McAllister defeated Okasa. However McAllister refused to deliver the coup de grâce. Okasa would recover from his injuries and would return to menace the pair several times over the course of the series.