Murder on the Links

Warning: Wikipedia contains spoilers.

In this book, Hercule Poirot receives a telegram from millionaire Paul Renauld, begging him to come to his estate in France. When Poirot arrives, Renauld is dead, his body found stabbed, lying on a golf course. His wife claims he had been kidnapped by some mysterious Chileans. It turns out that Renauld had been planning to fake his own death, but things (quite obviously) had gone disastrously wrong.

The book is notable for a subplot in which Arthur Hastings meets his future wife, Dulcie Duveen.