The Improvement is the second phase of the plot attempted by Mr. Curtain in The Mysterious Benedict Society. Once the turbines in Stonetown Harbor have generated enough energy, he programs the Whisperer to start sending out the messages directly, instead of relying on radio signals to carry them. This means that everyone is hearing them, even when no devices that rely on those radio signals are on.

In some cases, for people who have an exceptionally strong love of truth (Constance), this power boost means they are able to hear voices instead of the irritable feeling most others receive (Reynie, Sticky, and Kate).