"Perhaps your little girl knows where her father is," said Rolfe maliciously. "No, she doesn't," replied Mrs. Hill with some spirit. "You can ask her if you like." Rolfe was suddenly struck with an idea and he decided to test it. "I won't wait--I've changed my mind. But if your husband comes in tell him not to go to bed until I've seen him. I'll be back." "Yes, sir," she replied. "Do you think he was going to Riversbrook?" he asked. The woman flushed suddenly and then went pale. She knew as well as Rolfe that her husband was strictly forbidden, pending the trial, to go near the place of his former employment, and that the police had relieved him of his keys and taken possession of the silent house and locked everything up. "No, sir," she replied, with trembling lips, "Mr. Hill hasn't gone over there." "How can you be certain, if he didn't tell you where he was going?" asked Rolfe. "Because it's the last place in the world he'd think of going to," gasped Mrs. Hill. "Such a thought would never enter his head. I do assure you, sir, Mr. Hill would never dream of going over there, sir, you can take my word for it." Rolfe walked thoughtfully up High Street. Was it possible that Hill had gone to his late master's residence in defiance of the orders of the police? If so, only some very powerful motive, and probably one which affected the crime, could have induced him to risk his liberty by making such a visit after he had been commanded to keep away from the place. And how would he get into the house? Rolfe had himself locked up the house and had locked the gates, and the bunch of keys was at that moment hanging up in Inspector Chippenfield's room in Scotland Yard. But even as he asked that question, Rolfe found himself smiling at himself for his simplicity. Nothing could be easier for a man like Hill--an ex-criminal--to have obtained a duplicate key, before handing over possession of the keys. Rolfe had noticed with surprise when he was locking up the house that the French windows of the morning room were locked from the outside by a small key as well as being bolted from the inside. Hill had explained that the late Sir Horace Fewbanks had generally used this French window for gaining access to his room after a nocturnal excursion. Rolfe looked at his watch. It was nine o'clock. He decided to go to Hampstead and put his suspicions to the test. It was quite possible he was mistaken, but if, on the other hand, Hill was paying a nocturnal visit to Riversbrook and he had the luck to capture him, he might extract from him some valuable evidence for the forthcoming trial that Hill had kept back. And Rolfe was above all things interested at that moment in making the case for the prosecution as strong as possible.