What impact does the Whisperer have on the plot?

The Whisperer plays a critical role in the plot as it is the main mechanism through which Mr. Curtain exerts his control over the children and the society at large. This makes it central to the conflict faced by the members of the Mysterious Benedict Society. The Whisperer's ability to influence thoughts and actions creates a sense of urgency that drives the Society into action, prompting them to develop strategies to counteract its effects and ultimately confront Mr. Curtain's plans. The presence of the Whisperer intensifies the stakes, making the characters' mission vital to liberating not just themselves but also other children from Mr. Curtain's sinister influence. Hence, the Whisperer is instrumental in shaping the narrative and the development of the plot.