Having danced briefly in D.W. Griffith's World War I melodrama Hearts of the World, Texas-born Mary Hay was perhaps not the most obvious choice to play the important role of Kate Brewster in Way Down East (1920). But Hay resembled Griffith actress Clarine Seymour and proved a more than adequate replacement when Seymour suddenly perished from what were rumored to be aftereffects of the film's brutal winter scenes. Hay went on to marry Way Down East's genial juvenile lead Richard Barthelmess, and together they later produced and co-starred in New Toys (1925), a screen version of a popular New York play. Also in the cast was a very young Clifton Webb, with whom Hay would form a dance act later that year. She seems to have retired from show business when the vaudeville act was dissolved.