The Lost Mine

Hercule Poirot investigates the murder of Wu Ling, an agent for Burma Mines Ltd. The mine's location was lost; the only clue to its location is in old papers. Wu Ling agreed to negotiate a sale of the papers and travelled to England to complete the transaction. Mr Pearson was to meet Wu Ling at the train in Southampton but Wu failed to appear. The police were contacted and the next evening Wu Ling's body was found floating in the Thames.

Poirot interviews a young bank clerk called Charles Lester, who called for Wu Ling at his hotel on the morning of the disappearance. Mr Lester told a story of having been met by Wu's servant, who took them in a taxi to Limehouse where Lester became nervous and got out of the taxi before they reached their destination. Lester's story is revealed as a lie and he is arrested, but the papers about the mine are not found.

Poirot finds the papers – Pearson has them. He had met Wu Ling in Southampton and taken him directly to Limehouse, where Wu Ling was killed. Hearing of Lester's invitation to visit the hotel from Wu Ling himself, Pearson set the young man up to take the blame for the murder. Pearson is arrested and Poirot becomes a shareholder in a Burmese mine.