1. The famous saying of the crime-fighting vigilante, The Shadow.

2. The introduction from The Shadow radio program "Who knows what evil lurks in the hearts of men? The Shadow knows!" spoken by actor Frank Readick Jr., has earned a place in the American idiom. These words were accompanied by an ominous laugh and a musical theme, Camille Saint-Saëns' Le Rouet d'Omphale ("Omphale's Spinning Wheel", composed in 1872). At the end of each episode The Shadow reminded listeners that, "The weed of crime bears bitter fruit. Crime does not pay... The Shadow knows!"

Source: 1. en.wikipedia.org/wiki/The_Shadow; 2.www.internationalhero.co.uk/s/shadpulp.htm
Powers/Abilities: The Shadow possesses incredible physical abilities. He possesses astonishing reflexes and is an incredible marksman with a gun. He also has incredible muscular control and can slip his body through the bars of a prison cell like a contortionist or can actually distort and alter his very facial features at will by manipulating his facial muscles. He can also survive for hours without air and was also ambidexterous. He is regarded as highly experienced in various disciplines of hand to hand combat as well.
His greatest power is his ability to “cloud men’s minds”. He can hypnotize people instantly so that he can move as an invisible shadow. He can also hypnotize people so they forget things or to command them to perform certain acts (he once forced a criminal to write a detailed account of his past crimes).He is an expert in many different languages and is also a master ventriloquist (he can project or “throw” his voice).
He is also a master of disguise and has been known to impersonate others, even fooling their friends and family members. The Shadow is apparently an expert aircraft pilot and skilled in infiltration and information gathering techniques due to his experience as an intelligence agent.
He wields a pair of .45 pistols and employs a fleet of automobiles and aircraft in his various operations.

"Who knows what evil lurks in the hearts of men? The Shadow knows!"
by The Centurion January 10, 2013
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