The screaming of people from all directions in the Gare Du Nord is a scene. It is chaotic Paris at its finest. I grab my brown leather luggage and head towards the ticketing office. I board the train to escape the train station. After forty minutes or so, the train has finally reached its optimal speed. I dress for lunch and head to the dining room located in the second car.
I arrive at the dining room and see three groups of people already seated. The first group is a family: a mother and father with their two sons. They are probably from the United States, enjoying a family vacation. The second and third groups are all couples. I greet everyone, since they are going to be my neighbors for a week.
I sit down and start ordering food. I order a cold sparkling champagne, two appetizers, and a medium-rare steak. The cold champagne slightly intoxicates me. After my second appetizer is set on the table, the last passenger of the train comes in. He presents himself as a “skilled” doctor from Berlin. His tone and appearance is dark, a type of person I have difficulty investigating.

After lunch, I go to the bar to grab some water. When I enter the bar, the American man is enjoying a conversation with his wife. The man notices me and welcomes me into the seat right next to him. I formally introduce myself.
“Nice to meet you. I am Daniel Elwood from London.”
He shakes my hand and says, “Honored to meet you, Dr. Elwood. I still can’t get over the fact that I am meeting the best detective in the world! Do you want a glass of whiskey? It's from the States.”
“Yes, please. It would be a pleasure. However, I must warn you that I get drunk rather easily. Please excuse me if I do,” I respond.
“Absolutely fine, as long as you're enjoying the drink,” he exclaims.
We make a toast and I take a sip, enjoying the smoothness of the drink.
It is 4:38 a.m., and my body feels stiff. I open my eyes to see that I am back in my cabin. I don’t remember anything. I sit up and go to the powder room to wash up. While I am washing my hand, I surprisingly see dry blood on my ring. It also seems peculiar that the red ruby on the ring has been slightly chipped off.  Even though it strikes me as odd, I shrug it off and leave the cabin just to stretch my body. I walk from my cabin to the lounge. In the lounge, only the lamp lights are on. The smell of this car is off. It is a foul odor that I could slightly recognize. I sit in the third seat and drink a glass of water. A sharp pain in my head suddenly triggers images of last night. The only conversation I recount is the beginning, when the man and I get into a heated argument about American politics.
I pick up a book, Strange Case of Dr. Jekyll and Mr. Hyde, a science-fiction thriller that revolves around a character who is diagnosed with multiple identity disorder, otherwise known as the Dissociative Identity Disorder (D.I.D). As I am finishing page 58 of the book, the German doctor, Adrian Krämer, enters the lounge and strikes up a conversation.
“Good morning, Dr. Elwood. You woke up quite early.”
“Indeed doctor, did you sleep well?” I ask.
“Yes, I did. I did hear some odd noise outside my cabin last night, probably because my cabin is so close to the lounge and the bar.”
He glances at the book and excitedly exclaims, “That is a great book. As a matter of fact, I am currently conducting a study on D.I.D. In Germany, we have about 7-10 people who have this disorder. I try to find the symptoms of the disorder and the psychological therapy that would alleviate this problem.
“That is very interesting. What are some symptoms or things that cause the disorder?” I ask.
“Well, so far we have found out that traumatic experiences cause this disorder. It can be triggered in many ways, one of the most common ways of triggering another personality would be heavy drinking. In addition, one of the most interesting things about this disorder is that only some, like two or three of the people who have this disorder, know that they themselves have this disorder by remembering small occurrences of flashbacks,” he replies.
The smell in the room seemed to exponentially grow. “Sorry, but is it just me, or is there a stench in the room?” I ask.
“I smell it, too,” he responds.
I walk down the aisle carefully. As I get closer to this stench, I see small blood stains. I walk a bit faster, and before I know it, I am in front of a lifeless body... The American man is dead.
The next few hours are a blur. His family rushes towards the dead body, the doctor examines his death, and the conductor is notified to stop to conduct safety checks. Everyone in the train goes back to their individual rooms to seek safety.
It is 10:24 a.m. The train is moving. We are still in the middle of the Alps. I hear footsteps and someone knocks on my door. I unlock the lock and see the conductor and the doctor. They ask me to join them in the conductor’s room. I reluctantly agree.
“Please Dr. Elwood, we need to resolve this case. We have approximately six days until we arrive in Germany and we are in a hurry. There are no German detectives that are as skilled as you,” the doctor pleads.
“Sir, I am soon retiring as a senior detective. I came aboard to take refuge from my hectic schedule. I wish to not take part; however, I will contact one of my colleagues, if that is what you wish.”
Inexplicably, I change my mind.
“I will take this case. Dr. Krämer, I need you to write me the description of his death. I need the conductor to set up appointments with everyone in this train, including all the workers.” 
I head to the murder scene. I first locate where the blood is coming from. The stomach seems to be cut with a small, sharp object, and I notice a red, sparkly gem in the left side of his stomach. I retrieve it, as it can be crucial evidence of the mysterious death. The red ruby looked very similar to the one I have in my ring. Coincidentally, it is exactly the same as the chipped off piece. For now, I set this evidence aside.
The doctor tells me that he estimates that the death of the man occurred around 12:00 a.m., the same time that I had whiskey with the American man. I rush towards the butler, the only person who is able to know everyone who went in and out their room.
“Were there anyone besides me in the hallway from 12:00 a.m. to 2 a.m.?” I ask.
“Um, I believe you were the only one,” he responds.
“Is there any other way one can enter or escape inside their room?” I ask again.
“No sir, our cabin is sealed,” he answers.
Based on the claim, the American man could have committed suicide, or one of the staff members could have murdered him. There is one other way, but that simply is impossible.
I walk around the murder scene, trying to find the last piece of evidence. I search the ground, checking if there is something I left out. The conductor enters the room, helping me find more evidence.
“Mr. Elwood, I am not sure if this is helpful but here is a small paper I found inside the pocket of the dead passenger,” he claims.
I look at the paper and the world goes pitch black. The evidence and my conclusion only lead up to one murderer. I can’t be wrong. I have investigated over 800 cases throughout my life; it is impossible for me to be wrong. I somehow find my way to the room.
It hits me that I am the only possible murderer in the train. But how?
Flashbacks of my conversation with the doctor pass through my mind. “Many patients with D.I.D tend to have their other personality pop up when they are drunk.” All along, I had the symptoms of D.I.D, turning into a different person every time I am drunk. 
All my life, I have put murderers behind bars. I have labeled murderers as the worst form of mankind, and yet, I stand here as one of them. I simply cannot accept the fact that I am the murderer. My mind feels blank, unable to process the event that has occurred. My body automatically moves me to the last car of the train. I open the train door. The fresh breeze of the Alps hits me while I stand across the tracks, still unable to accept myself as a murderer.
The biting wind of the Alps gushes into the last car of the train. The paper left by Dr. Elwood is left under the whiskey cup. The paper reads: Passenger’s Room: Suite #1, Dr. Elwood. The red blood stains cover the left corner of the paper, and when the paper is turned over, it simply reads: Yes, you have solved the case.