Based on another work of Agatha Christie and featuring Belgian detective Hercule Poirot, the game continues the hidden-object casual adventure game series started with Agatha Christie: Death on the Nile.
Relaxing at St. Loo's café on Cornwall Coast of England in the early Autumn of 1927, Hercule Poirot and his faithful companion Hastings occasionally meet Magdala "Nick" Buckley, the last female person in a long line of Buckleys inhabiting End House. From the conversation with her you understand that during past week she has happily escaped from three situations lethal for her. So famous Poirot decided to uncover the mystery and to find out who is trying to kill Miss Buckley before it's too late.
As you play through 13 investigations, you will uncover clues. At the end of the game, you will reveal whodunit! During each investigation, you will go through different locations of St. Loo and look for items on Poirot's list. Each location is a static screen, sometimes with animated parts on it. As you find items, Poirot eliminates them from the investigation or identifies them as important clues. Finding all the objects in certain locations will reward you with a Clue Card. Each Clue Card reveals a statement from a suspect or colleague. They are stored in your Clue Room and may be used to help solve the mystery.
At the end of each investigation, you can solve a bonus puzzle based on the uncovered clues. Each puzzle is different from normal gameplay, and features constructing the mechanism from its parts, decode the letter from Miss Lemon with given words, composing newspaper with cut pieces, opening the safe, etc. Completing a bonus round will reveal more information about the case. The cut-scenes between or during investigations are shown in comics art-style that untwist the plot.
You have 25 minutes to complete each investigation. If you have difficulties with finding items, you may use one of five hints or move to another location and return back later. If you run out of time, you must restart your searches for the beginning of current investigation.