〃He　is　a　very　remarkable　person；〃　said　Knighton　slowly；　〃and　has　done　some　very　remarkable　things。　He　has　a　kind　of　genius　for　going　to　the　root　of　the　matter；　and　right　up　to　the　end　no　one　has　any　idea　of　what　he　is　really　thinking。　I　remember　I　was　staying　at　a　house　in　Yorkshire；　and　Lady　Clanravon's　jewels　were　stolen。　It　seemed　at　first　to　be　a　simple　robbery；　but　it　pletely　baffled　the　local　police。　I　wanted　them　to　call　in　Hercule　Poirot；　and　said　he　was　the　only　man　who　could　help　them；　but　they　pinned　their　faith　to　Scotland　Yard。〃

〃And　what　happened？〃　said　Katherine　curiously。

〃The　jewels　were　never　recovered；〃　said　Knighton　drily。

〃You　really　do　believe　in　him？〃

〃I　do　indeed。　The　te　de　la　Roche　is　a　pretty　wily　customer。　He　has　wriggled　out　of　most　things。　But　I　think　he　has　met　his　match　in　Hercule　Poirot。〃

〃The　te　de　la　Roche；〃　said　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