The Master follows the life of John Peter McAllister, an Air Force colonel stationed in Japan during World War II. While in Japan, McAllister became enthralled with the Ninja, and entered the sect, quickly becoming a ninja master himself. But when some of the younger masters use their skills for evil, McAllister left Japan for America, violating an oath he took.
Back in America, McAllister meets Max Keller, and trains him to be a ninja master as well. Together they set off to find McAllister's daughter, and fight evil along the way. But not far behind them are deadly assassins, led by Okasa, sent to kill McAllister for violating the oath of the sect.