This book is one of a series of reading books for children and young adults aged 11 and over who are struggling with reading. "Dark Man" is a fiction series for older children and young adults who have a reading age of approximately 7 to 8. Each book features the character Dark Man, a shadowy, brooding loner who shuns society, living in the shadows.

Recruited to play a part in a secret, cataclysmic struggle between good and evil, his continued mission is to seek out an artefact, a Golden Cup, which can channel limitless power and energy. Opposed to him, and also seeking to find this cup of power, is a sinister and corrupt organisation, The Shadow Masters.The book has a strong plot to engage the reader, however reluctant, and features dark evocative illustrations. The simple, carefully written text (around 1,100 words) focuses on the most common words, providing access for even the poorest readers.

In "Killer in the Dark" the Dark Man watches a dark, shadowy killer. A living shadow. The Dark Man must find out what it is and stop it, before more people are killed.