They walked briskly, one behind the other, and she stopped at the apothecary’s door. Naturally, Thorpe had a key, as he had to all doors. He opened the door and stepped in, and they followed behind, crowding into the small space. It was lined with cupboards right up to the ceiling. Each had its brass-bound keyhole, even the drawers beneath the shelf.

"I am afraid I do not have keys to these," Thorpe said reluctantly. "But as you may see, it is all kept with the utmost safety. I do not know what more we can do, except employ a second apothecary so that there is someone on duty at every moment. Obviously, we may require medicines at night as well as during the day, and no one man can be available around the clock, however diligent."

"Who has keys at night now?" Robb asked.

"When Mr. Phillips leaves he passes them to me," Thorpe replied with discomfort, "and I give them to the senior doctor who will remain here at night."

"From your wording I assume that is not always the same person," Robb concluded.

"No. We do not operate during the night. Seldom does one of the surgeons remain. Dr. Beck does, on occasion, if he has a particularly severe case. More often it will be a student doctor." He seemed about to add something, then changed his mind. Perhaps he felt the whole hospital under accusation because one of its nurses had been given the opportunity to steal, which had resulted in murder. He would have liked to distance himself from it, and it was plain in his expression.

"Who gives the medicine during the night?" Robb asked.

Thorpe was further discomfited. "The doctor on duty."

"Not a nurse?" Robb looked surprised.

"Nurses are to keep patients clean and comfortable," Thorpe said a trifle sharply. "They do not have medical training or experience, and are not given responsibilities except to do exactly as they are told." He did not look at Hester.

Robb digested that information thoughtfully and without comment. Before he could formulate any further questions the apothecary entered, closely followed by Callandra, who avoided Hester’s eye.

"Ah!" Thorpe said with relief. "Phillips. Sergeant Robb here believes that a considerable amount of medicine has gone missing from our supplies, stolen by one of our nurses, and that this fact has provided the motive and means for her to be blackmailed." He cleared his throat. "We need to ascertain if this is true, and if it is, precisely what amounts are involved, how it was taken, and by whom." He had effectively laid the fault, if not the responsibility, at Phillips’s door.

Phillips did not answer immediately. He was a large man, rather overweight, with wild dark hair and a beard severely in need of trimming. Hester had always found him to be most agreeable and to have a pleasing, if somewhat waspish, sense of humor. She hoped he was not going to get the blame for this, and she would be painfully disappointed in him if it were too easy to pass it onto Cleo.