The mystery of the cheap apartment

Synopsis

With the intercession of her great-aunt Marple, Maybelle obtains her father's permission to become a detective and knocks on the door of Poirot's detective office, only to be flatly refused. Unwilling to give up, Maybelle visits a real estate agent to decide where to live. She gets information about a very cheap, fine property and goes for an interview, but is turned down the moment she gives her name, and the place goes to the Robinson couple, who arrived right after. Sensing something about this affair, Poirot rents a room in the same building and has Hastings keep watch...