By day, Ida is a quiet, standoffish maid in the employ of spoiled Lucinda Belmote. By night, she is the infamous sneak thief known as the Rat Prince, terrorising the wealthy inhabitants of Loxport; especially Lucinda's lecherous suitor, Lord Devon Casterbury. Soon the boundaries between her dual lives begin to blur, as her mask begins to drop around a delightful waitress and a charming jeweller who both insist on befriending Ida. All the while...