The Green Hornet is a fictional character, a masked crime-fighter, created by George W. Trendle and Fran Striker, with input from radio director James Jewell, in 1936. Since his radio debut in the 1930s, the Green Hornet has appeared in numerous serialized dramas in a wide variety of media.
Though various incarnations sometimes change details, in most versions the Green Hornet is the alter ego of Britt Reid, wealthy young publisher of the Daily Sentinel newspaper by day. But by night Reid dons the long green overcoat, green fedora hat and green mask of the mysterious "Green Hornet" to fight crime as a vigilante. Reid is accompanied by his loyal and similarly masked partner and confidant, Kato, who drives their technologically advanced car, the "Black Beauty". Though both the police and the general public believe the Hornet to be a criminal, Reid uses that perception to help him infiltrate the underworld, leaving behind for the police the criminals and any incriminating evidence he has found.
More on the Hornet here from whence I borrowed the ad above.