Whispers Under Ground takes the place of the third novel in the Peter Grant series. In this novel; the story starts from a Murder investigation at the Baker Street Underground Station, where the victim James Gallagher was critically stabbed and murdered with a pot shard. Seeing the use of this unusual weapon and the local investigation; Peter Grant’s suspicions rise. While investigating deeper into the case; Peter Grant finds a secret world that lies beneath the streets of London that is inhabited by demi-human and supernatural beings. The investigation doesn’t end there; as they dig deeper they unfolds more secrets and leads to the case.