Though the facts of Leon Theremin's life merit this feature film, director Steven M. Martin chooses to focus on Theremin's eponymous invention, a strange musical instrument which predated the synthesizer in the field of electronic sound. That skews the film toward Theremin as a contributor to the arts and away from his advancements in electronic surveillance and eavesdropping. It also gives Martin a chance to structure part of his film around a reunion of Theremin and his most famous pupil, Clara Rockmore, who almost steals the show from her aging mentor. (He died before the film was released; Rockmore died in 2001.) Bringing electronic music pioneer Robert Moog, plus rock musicians Brian Wilson and Todd Rundgren, into the mix also provides ingratiating touches, but the film never feels like it's dumbing down its subject. Martin is a true proselytizer for Theremin's place in history, and the film makes its case in a wholly convincing and entertaining fashion.