While you may never have heard of the ondes Martenot, you may have heard the evocative tones that emit from this unique electronic instrument. Its distinctive timbre has been used in soundtracks for the sci-fi TV show Thunderbirds as well as feature films from Lawrence of Arabia to There Will Be Blood. The French musician and educator Maurice Martenot was a telegraph operator during World War I, when he was transfixed by the sounds emanating from radio vacuum tubes. He spent the rest of his life perfecting his ondes, an instrument that converts electricity into music, and one so mysterious that its secrets are still being unraveled.