Mistress Monique has been retained by two sisters, Nancy, and Felice, to instill some discipline into one of their employees. Poor little Cindy is accused of insolence and lying and is subjected to the Mistress's severest punishments including suspension, clamps, whips, and clothespins. Cindy not only bravely survives the ordeal, but informs the Mistress that she is not an employee, but a step sister imprisoned as a slave. The final straw is when the sister's check to the Mistress bounces. The sisters visit Monique's dungeon to pick up Cindy only to find that they have become the prisoners themselves, and must face the Mistress's vengeful wrath!