Katherine thoughtfully； 〃so you really think he did it？〃
〃Of course。〃 Knighton looked at her in astonishment。 〃Don't you？〃
〃Oh yes；〃 said Katherine hastily； 〃that is； I mean； if it was not just an ordinary train robbery。〃
〃It might be； of course；〃 agreed the other； 〃but it seems to me that the te de la Roche fits into this business particularly well。〃
〃And yet he has an alibi。〃
〃Oh； alibis！〃 Knighton laughed； his face broke into his attractive boyish smile。
〃You confess that you read detective stories； Miss Grey。 You must know that anyone who has a perfect alibi is always open to grave suspicion。〃
〃Do you think that real life is like that？〃 asked Katherine； smiling。
〃Why not？ Fiction is founded on fact。〃
〃But is rather superior to it；〃 suggested Katherine。
〃Perhaps。 Anyway； if I was a criminal I should not like to have Hercule Poirot on my track。〃
〃No more should I；〃 said Katherine； and laughed。
They were met on arrival by Poirot。 As the day was warm he was attired in a white duck suit； with a white camellia in his buttonhole。
〃Bonjour； Mademoiselle；〃 said Poirot。 〃I look very English； do I not？〃
〃You look wonderful；〃 said Katherine tactfully。
〃You mock yourself at me；〃 said Poirot genially； 〃but no matter。 Papa Poirot； he always laughs the last。〃
〃Where is Mr Van Aldin？〃 asked Knighton。
〃He will meet us at our seats。 To tell you the truth； my friend； he is n