The　eyes　of　the　two　men　met。

〃A　well…known　horse；　eh？〃

〃No；〃　said　Poirot；　〃it　is　what　our　friends；　the　English；　call　a　dark　horse。〃

〃Ah！〃　said　M。　Papopolous　thoughtfully。

〃Now　we　must　step　across　to　the　Casino　and　have　our　little　flutter　at　the　roulette　table；〃　cried　Poirot　gaily。

At　the　Casino　the　party　separated；　Poirot　devoting　himself　solely　to　Zia；　whilst　Papopolous　himself　drifted　away。

Poirot　was　not　fortunate；　but　Zia　had　a　run　of　good　luck；　and　had　soon　won　a　few　thousand　francs。

〃It　would　be　as　well；〃　she　observed　drily　to　Poirot；　〃if　I　stopped　now。〃

Poirot's　eyes　twinkled。

〃Superb！〃　he　exclaimed。　〃You　are　the　daughter　of　your　father；　Mademoiselle　Zia。　To　know　when　to　stop。　Ah！　that　is　the　art。〃

He　looked　round　the　rooms。

〃I　cannot　see　your　father　anywhere　about；〃　he　remarked　carelessly。　〃I　will　fetch　your　cloak　for　you；　Mademoiselle；　and　we　will　go　out　in　the　gardens。〃

He　did　not；　however；　go　straight　to　the　cloak…room。　His　sharp　eyes　had　seen　but　a　little　while　before　the　departure　of　M。　Papopolous。

He　was　anxious　to　know　what　had　bee　of　the　wily　Greek。　He　ran　him　to　earth　unexpectedly　in　the　big　entrance　hall。

He　was　standing　by　one　of　the　pillars；　talking　to　a　lady　who　had　just　arrived。　The　lady　was　Mirelle。

Poirot　sidled　unostentatiously　round　the　room。　He　arrived　at　the　other　side　of　the　pillar；　and　unnoticed　by　the　two　who　were　talking　together　in　an　a