The Little Murders of Agatha Christie

The Cat and the Mice (Cat Among the Pigeons) (1x5)

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A mysterious murder with no apparent motive was committed near an institution for young girls good chic good kind. And here is our dear Commissioner Larosière and the unpayable Lampion landing in the middle of a band of more or less charming mice in search of a cat that plays on their nerves. Unless the cat in question is simply... one of the mice.