Singer Mary Smith McClain (August 27, 1902 - April 4, 2000) was one of West Virginia's few blues legends. Her career was long, but it wasn't until she was in her 80s and 90s that she received the recognition she deserved. She performed at Carnegie Hall, the White House, the Apollo Theatre, the Cotton Club, and she toured Europe three times.

McClain was born Mary Smith in Huntington. At 13, desperate to escape beatings from her stepmother, she disguised herself as a boy, hopped a train and began performing in the circus. Throughout the 1920s and 1930s she performed in medicine and minstrel shows. In the 1940s, she took the name "Diamond Teeth Mary" when she had diamonds from a bracelet implanted in her front teeth. Over the years, McClain shared the stage with such well-known performers as Billie Holiday, Sarah Vaughan, Big Mama Thornton, Ray Charles, Duke Ellington and Bessie Smith, who was her half-sister.

In 1960, she settled in Bradenton, Florida, and married Clifford McClain, where she became a popular gospel singer. It wasn't until Mary was 91 that she issued her first recording, "If I Can't Sell It, I'm Gonna Sit Down On It," and in 1983, she was featured in the documentary Free Show Tonight.

McClain was one of the first recipients of the Florida Heritage Award, and a play about her life premiered at the 2000 Florida Folk Festival. She continued to perform until her death in 2000, appearing at regional blues festivals. At her request, her ashes were sprinkled on the railroad tracks at Huntington, where she hopped her first train. She was inducted into the West Virginia Music Hall of Fame in 2011.