Leon Theremin was a Russian engineer who invented the electronic musical instrument that bears his name, and his story is as strange as the music the thing produces. After experimenting with radio vacuum tubes, Theremin developed a machine (1917-20) whose pitch and volume could be controlled by the movements of the performer's hands -- without touching the instrument.
The instrument was demonstrated for Vladimir Lenin, who was so impressed he ordered their mass production and asked Theremin to give him lessons. In 1927 Theremin emigrated to the United States, where he patented the "Thereminvox" (1928) and contracted with RCA to market and distribute them. During the '20s and '30s Theremin worked in New York and associated with high society, and his instrument gained fame thanks in part to the classical performances of Clara Rockmore. In 1938 Theremin mysteriously disappeared from his New York apartment, reportedly spirited away by a group of Russian men.
Beginning in the 1940s the Theremin was used for movie soundtracks, and these days is most commonly associated with 1950s science fiction films (and with the 1960s pop song by The Beach Boys, "Good Vibrations"). The instrument enjoyed fame in the U.S. and the U. K., but the whereabouts of its inventor remained a mystery. As it turns out, he had been kidnapped by the Soviet secret police, imprisoned for seven years and then put to work for Soviet intelligence. The story of his life and of the development of his electronic instruments was recounted in the 1993 documentary film
While in New York, Theremin married Iavana Williams, an African-American ballet dancer... Theremins are still being produced today, in a variety of forms, notably by Robert Moog, inventor of electronic synthesizers. (Source)