"I'm not sure, Sir," said Sergeant Lee.
"Well give it some thought, Sergeant," said Inspector Zhang, as he headed for the door.
Miss Berghuis was deep in conversation with her head of security when Inspector Zhang and Sergeant Lee walked back into the sitting room, but they stopped talking immediately and looked expectantly at the two detectives.
Inspector Zhang walked over to the window and turned to face the hotel staff. "So, to continue, Mr. Carr’s seventh and final locked room scenario involves a situation where the victim is assumed to be dead before he or she actually is. That is the reverse of situation number five of course, where the victim is dead, but presumed to be alive."
"So that would mean that Mr. Wilkinson wasn’t actually dead when Mr. Chau went into the room?" asked Miss Berghuis.
"He was," said the waiter. "I’m sure he was dead."
"But you’re not a doctor, Mr. Chau," said Inspector Zhang, "In the confusion, it might have looked as if he was dead but the actual murder was committed later."
"That’s impossible," said Mercier. "He was definitely dead when I got here."
"And you were here soon after the waiter made the call to reception?"
Mercier nodded. "You saw the CCTV footage. Everybody was there within a few minutes at most."
"He was definitely dead," agreed the manager. "You only had to look at the body. At the blood."
"But there was a moment when the waiter was alone with the body," said Inspector Zhang. "When he made the phone call. At that moment he was alone in the room with Mr. Wilkinson, and we have only Mr. Chau’s word that Mr. Wilkinson was dead."
"I didn’t kill him," said Mr. Chau hurriedly, his eyes darting from side to side.
"I didn’t say that you did," said Inspector Zhang. "I merely stated that you were alone with Mr. Wilkinson and you had the opportunity of killing him if he hadn’t been dead already. It is one way of solving a locked room mystery. The room is locked, but the person who discovers the body is the killer. He kills the victim then calls for the police." He shrugged. "It happens, but I do not think it happened in this case."
The waiter looked relieved and loosened his shirt collar.
"Besides, if you did kill Mr. Wilkinson, where is the knife?" asked Inspector Zhang.
"Actually Inspector Zhang, we haven’t searched anyone yet," said Sergeant Lee.
"And there is no need to search Mr. Chau, Sergeant," said the inspector. "What we need to do now is to go back downstairs to the security office; for it is there that the solution lies."
"All of us?" said the manager. "Surely we don’t all need to go?"
"It is the tradition, Madam," said Inspector Zhang. "The detective gathers together the cast of characters and explains the solution to them before unmasking the killer."
The manager laughed, and it was like the harsh bark of an angry dog. "Inspector Zhang, this is not some country house where the butler did it. Just tell us who the killer is."
"It is not a country house, that is true, but a five-star hotel is the closest thing that we have in Singapore," said Inspector Zhang. "Now please humour me and accompany me down to the ground floor."
The inspector led them out of the room and down the corridor to the elevators. He took the first one down with Mercier, the waiter, Miss Berghuis and one of the two uniformed policemen. Sergeant Lee followed in a second elevator with the two assistant managers and the other uniformed policeman. They gathered together outside the security room and Inspector Zhang led them inside. He waved a languid hand at the chair in front of the monitors. "Mr. Mercier, perhaps you would do the honours."
The head of security sat down and ran a hand over his scalp. "We’ve already looked at the CCTV footage," he said.
"We looked, but did we really see what happened?" asked the inspector. He waited until everyone had gathered behind Mercier’s chair before asking him to begin the recording from the point at which Mr. Wilkinson and the prostitute stepped out of the elevator.
"Here we can see Mr. Wilkinson and his guest arriving at eight-thirty," said Inspector Zhang. "Very much alive, obviously."
He watched as Wilkinson and the woman went inside. "She left an hour later. Please skip to that point, Mr. Mercier."
Mercier tapped a key and the video began to fast forward. He slowed to normal speed just before nine-thirty in time to see Ms. Lulu leave the room.
"Now, at this point Mr. Wilkinson ordered his club sandwich and coffee from room service, so again we know that he is still very much alive."
"So who killed him?" asked Miss Berghuis. "If the woman left the room and no one goes in before the waiter, who stabbed him?"
"That is an excellent question, Madam," said Inspector Zhang.
"But can you answer it, inspector?" asked the manager, tersely.
"I think I can," said Inspector Zhang. "They key to solving this mystery lies in understanding that it is not who goes into the room that is important. It is who does not go in."
"That doesn’t make any sense at all," said the manager crossly.
"I beg to differ," said Inspector Zhang. "It makes all the sense in the world. It is as Sherlock Holmes himself says in Arthur Conan Doyle's masterpiece The Adventure Of Silver Blaze, it is the fact that the dog did not bark that is significant."
"We do not allow dogs in the hotel," said Mercier. "There are no pets of any kind."
Sergeant Lee looked up from her notebook, smiling, and Inspector Zhang sighed. "I was using the story as an example to show that it is sometimes the absence of an event that is significant, which was the case in the Adventure of Silver Blaze. If I recall correctly it was Inspector Gregory who asks Sherlock Holmes if there is anything about the case that he wants to draw to the policeman’s attention. Holmes says yes, to the curious incident of the dog in the night-time. That confuses the inspector who tells Holmes that the dog did nothing in the night-time. To which Holmes replies, “That was the curious incident.” Do you understand now, Madam?"
She shook her head impatiently. "No inspector, I am afraid I do not."
"Then, Madam, please allow me to demonstrate," said Inspector Zhang. He put a hand on Mercier’s shoulder. "Please, Mr. Mercier, fast-forward now to the point where the waiter arrives with the room service trolley."
"This is a waste of time," said Mercier. "We did this already."
"Please humour me," said the inspector.
Mercier did as he asked and they all watched as the video fast-forwarded to the point where Mr. Chau arrived with his trolley and began knocking on the door.
"Normal speed now, please, Mr. Mercier. The video slowed as they watched the waiter use his key card to enter the room.
"At this point Mr. Chau is discovering the body and calling down to reception." Inspector Zhang waited until the waiter appeared at the door and began pacing up and down. "As you can see, no one enters the room until the hotel staff appear." On the screen Miss Berghuis and her staff appeared and they all hurried into the room. "At this point you phone the police," said the inspector, turning to Miss Berghuis. The manager nodded. Inspector Zhang patted Mercier on the shoulder. "So now fast-forward until my arrival, Mr. Mercier, but not too quickly. And I want everyone to note that no one else enters the room until I arrive with my sergeant."
The door to the room remained closed for twenty minutes until Inspector Zhang and Sergeant Lee stepped out of the elevator.
"Normal speed now please, Mr. Mercier. Thank you."
Mercier pressed a button and the video slowed. Inspector Zhang walked up to the door and knocked on it. It opened and he went inside, followed by his sergeant. The door closed behind them.
"So, now we are inside, talking to you and assessing the situation. We talk, then I go to the bedroom with you, Miss Berghuis, I look at the body, I talk to you, I walk back to the sitting room, and then I walk out with Mr. Mercier." On the screen Inspector Zhang and Mercier walked out of the room and headed for the elevator.