Mamo is an ancient being of immense knowledge and wealth, bent on discovering the secret of eternal life. He is the main antagonist of Lupin III: Mystery of Mamo. He also appears briefly in one scene of the 2014 film, Lupin the IIIrd: Daisuke Jigen's Gravestone.
At some point in time, Mamo adopted the alias of Howard Lockewood: the world's richest man, in order to cover up many of his activities. Using the vast wealth and resources he had accumulated throughout his years, Mamo plotted to annihilate all life on earth and transform the planet into his own utopia, populated by those he had hand picked and saw fit. At first glance Mamo appears to be a shriveled imp but throughout the course of the film, it is revealed that his elfish body is merely part of a series of degenerate clones derived from what little remains of the original Mamo.