Murder on the Links by Agatha Christie

Murder on the Links Agatha Christie
We join Poirot when he is opening his post and has received a letter entreating him to go straight to France on an urgent mission. In parallel Hastings meets a beautiful girl  (we all know how susceptible he was) on the train – she is a circus double act with her sister and they are acrobats.
Poirot’s letter is from a businessman called Paul Renauld but when Poirot arrives at his house he finds him already dead. Renauld was abducted from his bed in the night by masked invaders but his body is found stabbed on the local golf course in a shallow grave.
However the housemaid remembers a mysterious visit from the neighbour Mrs Duveen and a fragment of a cheque is found. The murdered man’s son Jack quarrelled with him right before about his inheritance and choice of fiancé – was it him? The murder weapon seems to have been a custom item made from a piece of aeroplane but was it the only one? And if so who had the other?
Why was there a body of a tramp found just after the murder? And what was the conversation in the rose garden about? Last but not least why does the situation ring bells with Poirot of a similar case years ago as well as the appearance of Mrs Duveen?

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