This is Scott Joplin's famous ragtime serenade which was featured in the film "The Sting." The melodies are haunting and a bit melancholy. The tango rhythm in the left hand is overlaid by the right hand's ragtime syncopation, often in complex rhythms, and in "very slow march time." The right hand is required to play filled-out octave chords in some sections, and the left hand sometimes covers a wide range in "stride" styling. Keys of C Major and F Major.