The Double Traitor by E. Phillips Oppenheim

Selingman's supper party was in some respects both distinctive and unusual. Norgate, looking around him, thought that he had never in his life been among such a motley assemblage of people. There were eight or nine musical comedy young ladies; a couple of young soldiers, one of whom he knew slightly, who had arrived as escorts to two of the young ladies; Prince Edward of Lenemaur; a youthful peer, who by various misdemeanours had placed himself outside the pale of any save the most Bohemian society, and several other men whose faces were unfamiliar. They occupied a round table just inside the door of the restaurant, and they sat there till long after the lights were lowered. The conversation all the time was of the most general and frivolous description, and Selingman, as the hour grew later, seemed to grow larger and redder and more joyous. The only hint at any serious conversation came from the musical comedy star who sat at Norgate's left.

"Do you know our host very well? " she asked Norgate once.