This film is a retelling of the Cinderella fairy tale in a modern setting, with Mary Santiago (Selena Gomez), a high school student with ambitions of becoming a dancer, taking the role of Cinderella; Tami (Jessica Parker Kennedy) Mary's only friend as the fairy godmother; the cruel, self-obsessed, snobby, and washed-up pop singer Dominique Blatt (Jane Lynch) taking the role of the stepmother, even though she is just her legal guardian and Mary's mother was one of Dominique's dancers when she died and took Mary in as her legal guardian and make her Dominique's slave; The aggressive, obsessed, and equally snobby Britt (Emily Perkins) and air-headed Bree (Katharine Isabelle) as the two stepsisters; and Joey Parker, (Drew Seeley), now a famous celebrity and pop star has returned to school for his senior year and to remember why he started dancing, as Prince Charming. A school dance substitutes for the ball, with the role of the glass slipper filled by a Zune.[1]
Who is the modern day  stepmother?
washed-up pop singer Dominique Blatt