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![](https://image.tmdb.org/t/p/w342/6f4IVfbn8knb7RjdZlGLuW5guDc.jpg)
The Big Four
With the world on the brink of WWII, there is more political turmoil when it appears that the famous Peace Party is in fact a cover for the Big Four.
![](https://image.tmdb.org/t/p/w300/xAnaVnevwT1ODhWLGdrDYWcFG84.jpg)
![](https://image.tmdb.org/t/p/w300/qkKHndnjcb8Wxg0eEtRRFVqtkCS.jpg)
![](https://image.tmdb.org/t/p/w300/w0TJUPxZAqZdCC3W1VZ4axsdEkt.jpg)
![](https://image.tmdb.org/t/p/w300/e9gXJtjU9ryUWLy8OPnEJ7Kx4ZG.jpg)
Other episodes for this season
![Elephants Can Remember](https://image.tmdb.org/t/p/w300/940FguRXcWCSUMAM5AOul9wjLhd.jpg)
![The Big Four](https://image.tmdb.org/t/p/w300/onlwR121fgVVJn4OdNJPxeygQTs.jpg)
![Dead Man's Folly](https://image.tmdb.org/t/p/w300/7ADW3MIVfypT8eDcT7UBlLoIIF8.jpg)
![The Labours of Hercules](https://image.tmdb.org/t/p/w300/9ISRkkw47EztezHxRKCZ2aKdtKf.jpg)
![Curtain: Poirot's Last Case](https://image.tmdb.org/t/p/w300/ptNDuxfpm6d4tpC7riKzB6p950c.jpg)
With the world on the brink of WWII, there is more political turmoil when it appears that the famous Peace Party is in fact a cover for the Big Four.