Irregular Detective Mysteries Books in Order

This series begins with a neat idea and follows it through with real affection: what happens when one of Sherlock Holmes's former Baker Street Irregulars grows up and decides to become a detective himself? Westerson's answer is Tim Badger, once one of Holmes's street boys, now trying to build a respectable agency in late Victorian London. He is joined by Ben Watson, a sharp, scientifically minded friend from the East End whose surname is a private joke the books enjoy without leaning on too hard.

They are not Holmes and Watson, and that is the point.

Tim and Ben work under Holmes's distant patronage, not in his shadow. Holmes can advise, recommend, and occasionally intervene, but these books are about the people who stand just outside the famous circle and try to solve cases on their own terms. That gives the series room to feel like a Holmes pastiche without becoming imitation. Tim is capable but not infallible. Ben is thoughtful, practical, and essential to the partnership. Together they are learning the job as they do it.

The setting is classic Sherlockian ground, foggy streets, boarding houses, newspapers, sensation, but the series also leans into the popular fascinations of the 1890s. Seances, mummy unwrappings, kidnappings, strange country houses, and supposed vampires all fit naturally here. Westerson uses that penny-dreadful flavor well. The cases are dramatic and sometimes playful, but they still function as solid mysteries with suspects, motives, false turns, and social complications.

One of the best things about the books is the way they widen the lens beyond Holmes himself. Tim's class background matters. Ben's race matters. The doors open to them are not always the same doors that would open to Holmes or Dr. Watson, and the books are stronger for acknowledging that. Westerson does not turn the series into a lecture, but she does let Victorian London look like a place structured by status and prejudice as well as clue gathering and cleverness.

Ellsie Littleton, a journalist who moves around the edges of their cases, adds another useful angle. She helps keep the stories lively and reminds you that crime in this world is also performance, rumor, headline, and public story. That fits perfectly with a series built in part out of Holmes lore, where reputation matters almost as much as method.

The tone lands in a comfortable middle ground. These are lighter than Westerson's medieval books, but not flimsy. They have warmth, banter, and a fondness for the source tradition, while still giving Tim and Ben room to become more than a novelty concept.

If you like Sherlock-adjacent fiction but want new leads, not just another retelling, these books are a good choice. They offer familiar pleasures, gaslit London, odd cases, deductive work, while letting two less celebrated characters claim the spotlight for themselves.