"Mr. Blue" is a song by The Fleetwoods, released in 1959. It features a soft, melodic sound typical of the doo-wop genre, with harmonious vocals that convey a sense of longing and sadness. The lyrics tell the story of a man feeling blue due to lost love, expressing his emotions through a heartfelt narrative. The song became a hit, reaching number one on the Billboard Hot 100 chart. Its popularity has led to various covers and renditions over the years, solidifying its place in classic American music. "Mr. Blue" remains a nostalgic favorite for many listeners.