Umiko Wada has recently had quite enough excitement in her life. With her husband recently murdered and a mother who seems to want her married again before his body is cold, she just wants to keep her head down.
As a secretary to a private detective, her life is pleasingly uncomplicated, filled with coffee runs, diary management and paperwork.
That is, until her boss takes on a new case. A case which turns out to be dangerous enough to get him killed. A case which means Wada will have to leave Japan for the first time and travel to London.
Following the only lead she has, Wada quickly realises that being a detective isn't as easy as the television makes out. And that there's a reason why secrets stay buried for a long time. Because people want them to stay secret. And they're prepared to do very bad things to keep them that way...