Cinderella

Cinderella can refer to various works:
 * "Cinderella", the fairy tale best known as told by Charles Perrault.
 * Cinderella (1950), the Disney animated film and its sequels (2002, 2007)
 * Cinderella (1957), the musical film by Rodgers and Hammerstein and its remakes (1965, 1997)

If you are looking for a trope, that's Cinderella Circumstances.