One night, Arthur Bryant witnesses a drunk middle-aged lady coming out of a pub in a London backstreet. The next morning, she is found dead at the exact spot where their paths crossed. Even more disturbing, there's a twist: the pub has vanished and the street itself has changed. Bryant is convinced that he saw them as they looked over a century before, but the elderly detective has already lost the funeral urn of an old friend. Could he be losing his mind as well?Then it becomes clear that a number of women have met their ends in London pubs. It seems a silent, secret killer is at work, striking in full view...and yet nobody has a clue how, or why - or where he'll attack next. The likeliest suspect seems to be a mental patient with a reason for killing. But knowing who the killer is and catching him are two very different propositions. As their new team at the Peculiar Crimes Unit goes in search of a madman, the octogenarian detectives ready themselves for the pub crawl of a lifetime, and come face to face with their own mortality...