Marple's nephew offers her a holiday in London and she decides to go to Bertram's Hotel, a place where she used to stay when she was younger. While staying there, Marple notices that something odd is happening as there are a lot of people at the hotel that look alike. She cannot help herself and eavesdrops and observes the other guests as much as she can.

This story is slightly different as we do not know all that Marple knows and sees, plus the plot seems to come out of a spy story. I enjoyed it, but the end is both surprising and slightly disappointing. I was expecting more out of this one.