This book investigates the readiness of candidates for the National Investigator's Exam (NIE) by providing a simulated testing environment. Author David Pinfield utilizes his expertise in police training to construct a comprehensive mock examination that mirrors the structure and difficulty of the official assessment. The text serves as a diagnostic tool, allowing candidates to evaluate their knowledge of investigative procedures and legal frameworks within a constrained timeframe. By replicating the actual exam format, the book aims to reduce candidate anxiety and improve performance through repetitive, high-stakes practice.

Candidates and police training instructors frequently utilize this text as a standard preparatory tool for the NIE. Experts highlight the book's adherence to the official exam format as its primary value for students seeking to master the required material.