LitCharts assigns a color and icon to each theme in The Beggar’s Opera, which you can use to track the themes throughout the work.
Moral Corruption and Hypocrisy
Gender, Love, and Marriage
Class, Capitalism, and Inequality
Opera, High Art, and Performance
Summary
Analysis
In private, Polly remarks that Lucy is clearly pressuring her to drink because she wants to “pump some Secrets out of me.” So she won’t drink at all.
Polly correctly notices that something is wrong with Lucy’s cordial, but just like she has done with Macheath throughout the play, she naïvely underestimates exactly how evil Lucy can be.