"Listen, and I'll explain," she began to Mme. de Gallardon. "To-morrow evening I must go to a friend of mine, who has been pestering me to fix a day for ages. If she takes us to the theatre afterwards, then I can't possibly come to you, much as I should love to; but if we just stay in the house, I know there won't be anyone else there, so I can slip away."