A mysterious, malevolent force begins to terrorize London, leaving a trail of death and madness in its wake. The novel follows a group of individuals who become entangled in the investigation of a series of bizarre murders and disappearances, all seemingly connected to a strange, otherworldly entity. As the entity's influence grows, it preys on the characters' deepest fears and desires, blurring the lines between reality and hallucination. The narrative unfolds through multiple perspectives, revealing the escalating horror and the desperate attempts to understand and combat the unseen threat.

The Beetle is often cited as a significant work of early horror fiction, noted for its unsettling atmosphere and its exploration of psychological terror. Critics have pointed to its ambitious scope and its engagement with themes of the uncanny and the monstrous. While some contemporary reviews may have been mixed, its enduring presence in discussions of gothic and supernatural literature suggests a lasting impact. The novel's ability to evoke a sense of pervasive dread and its complex narrative structure continue to be points of discussion among readers and scholars.