Marion Lane And The Midnight Murder by T.A. Willberg

In 1958 London, a young apprentice at a clandestine detective bureau hidden beneath the city races to solve the locked-room murder of a colleague, a crime apparently committed with one of the agency’s own ingenious inventions. As suspicion falls on her mentor and the organization turns inward, she navigates treacherous tunnels, cryptic clues, and office politics to unmask a killer in their midst, risking her future and exposing long-buried secrets that threaten the agency’s survival.

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