As follow on from my previous article: Why Mary shot Sherlock.
I explain in more detail:
1. How we know that Mary did not intend to kill Sherlock from the position of the bullet wound. She shot him in the liver not the heart or the lungs.
2. Why she chose that particular spot above all other organs, she was not trying to kill him slowly.
3. Why Mary is a morally interesting character, and much more than just another villain
4. Why Sherlock forgave Mary
5. Why Mary was unhappy when she heard Sherlock had lived
Thank you to everyone who sent in questions, submission etc. My inbox is now overflowing. I aim to answer all you questions in one post.
The Anatomy of a Killing
To fully understand the reasons behind Mary shooting Sherlock and his subsequent survival, we must first work out where the bullet landed.
From the pictures of “dead” Sherlock in the scene, we can see that bullet hole is slightly to the right of the midline and under the nipple line. The nipple line in a man usually corresponds to the fifth intercostal space (i.e. the space between the 5th and the 6th ribs).
Estimating from the photographs of "corpse Sherlock", the bullet hole is around 1-2 cm right of the midline and at least 3-4cm below the nipple line. This is at least the 7th rib or the 7th intercostal space. This means that the bullet penetrated the upper part of Sherlock's liver, not his lungs and definitely not his right ventricle.
Even though both the lungs and the heart move down during inspiration, they do not move down that low even with very deep breaths and, if you look at the episode, Sherlock remains calm all the way to being shot. He is not taking any deep breaths at all. Therefore I do not buy the idea that because he was breathing in when he was shot, the bullet at that place would pierce his lung.
The liver is a vascular organ, though not as vascular as the spleen. From a surgical point of view, controlling liver bleeds is not extremely difficult, as evidence by the high survival rate of bullet wounds to the liver. At the position the bullet penetrated Sherlock’s body it is unlikely to have hit a major artery because the main artery supplying the liver (hepatic artery) splits up into many small arteries within the liver.
Most bullet wounds to the liver do not damage a major blood vessel, and can be managed conservatively or with simple surgical techniques.
In an analysis of 153 gunshot wounds to the liver: 105 patients (70%) the injuries to the liver were minor I.e. Did not produce life threatening bleeding. 93 patients required no treatment and 12 patients required simple suture of bleeding vessels. The mortality rate for the entire group attributed to liver injuries was 8% (12). Thus the chances of surviving a shot to the liver are 92 percent. Compare this to a thoracic gunshot wound which has a mortality rate of around 20-30%. Of the patients with wounds that did not damage a major blood vessel the survival rate of 100 percent.
Thus out of the all the organs Mary could have targeted, the liver provided the best survival rate.
If Mary truly wanted to kill Sherlock, she would have just shot him in the heart. It would only require her to change the angle of her gun by a fraction of a degree and she would not miss from that distance. If Mary was truly sadistic she would have shot Sherlock in the gut and thus give him acute infectious peritonitis on top of the blood loss. Mary did neither of these things.
The precise location of the shot was also very important. The liver is divided into eight surgical segments. Mary aimed for the left side of the liver, specifically the left most segment (number 2). The inferior vena cava usually runs to the right of segment 4a which is on the right of segment 2. The IVC usually travels 2.5 to 3 cm right of the midline. Unfortunately for Sherlock his vena cava was evidently further towards left and towards the midline than one would expect in a normal person, because the bullet must have hit his inferior vena cava in order to precipitate his cardiac arrest.
If the bullet hit a large vein instead of a large artery, there would not be great gush of blood but the wound will produce a thick steady flow, which is what we see in the episode.
The Logic of a Shooting
Now, if Mary didn't intend to kill Sherlock why did she not consider the position of the inferior vena cava and shoot Sherlock in a more lateral location?
The important thing to remember is that even most doctors do not remember precisely where the IVC runs in relation to the midline. I spent an entire year of my life studying anatomy in excruciating detail but I don't use that knowledge in my daily life as a doctor. I had to get out my anatomy atlas to find out where the IVC should be. I would not expect an assassin or a part time nurse to know this information off the top of their head and be able to use it accurately at such a stressedful time.
I do believe that Mary only remember that shooting someone in the liver had a very good survival rate. She did not remember the exact position of the IVC.
We must also remember that Sherlock was fully clothed at the point when Mary shot him. She needed to use his suit and the buttons on his shirt as landmarks to guide her estimating of the underlying anatomy. I am sure that as an assassin she knows how to use closing to estimate anatomy better than any doctor because we always have the option of asking patients to take off their clothes. If she chose to shoot Sherlock in a more lateral point, she would not have the guiding landmarks of his suit lapel or the two sides of the buttoned up shirt. She would only have a mass of black coat without close identifying landmarks to guide her eye. Therefore, from Mary's point of view it was safer to shoot Sherlock more laterally so she could aim as close to the guideline landmarks as possible.
Besides, as Mary wasn't intending to kill Sherlock but needed to incapacity him, she didn’t exactly have a great deal of choice in where to shoot Sherlock.The liver was the best choice out of a lot of bad choices.
She needed to incapacitate him, so that he couldn’t tell John and his injuries would hold John up enough for her to deal with Magnussen. Therefore she couldn’t just shoot him in a limb because he would still be able to function. The least dangerous alternative would be the chest/abdomen.
The heart must be avoided at all costs and shooting Sherlock in the lung would give him a tension pneumothorax (which is very deadly). Therefore there is only the abdomen to consider.
The most important thing to avoid in the abdomen is the abdominal aorta. It is largest artery in the body and even a small nick could kill Sherlock almost instantly. This is why Mary couldn’t shoot him straight in the middle of the abdomen because there would a good chance the bullet would go straight through him and hit the aorta in his back.
Now that the middle is out, Mary has a choice of left or right. To the left is part of the stomach and the spleen; to the right is the liver. Lower down are the intestines and the pancreases. Mary clearly wanted Sherlock to have the best chance at surviving, which is why she didn’t touch the stomach, the intestines or the pancreas. If any of these organs were damaged, Sherlock would develop life threatening inflammation inside his abdomen on top of the blood loss.
The spleen is quite hard to aim for, particularly as some of it is behind the stomach. Unlike on a model of the human body, your abdominal contents actually move around quite a lot. It is impossible to tell how much your stomach may be lying to the left or the right. The spleen needs an even better blood supply than the liver and bleeds just as much if not more than the liver when damaged. It also has a tendency to die rather quickly if there a lot of bleeding which is why when spleens are damaged we usually just take the entire organ out rather than just the bullet. It is perfectly possible to live without a spleen but you will have a deficient immune system and have a higher risk of dying from a blood clot.
This really only leaves the largest organ in the body – the liver and because it is so large, it is also much easier to aim for and you can function perfectly well with only half your liver. Thus Sherlock should not have had any long term problems relating to the bullet wound.
I have received many very emotive responses, mostly accusing me of defending a murderer
Firstly, Mary didn't murder Sherlock because Sherlock never died, he had a cardiac arrest which is very different from actually being medically dead.
Secondly, I am not suggesting that Mary's actions are morally acceptable. The point of my essay is to point out that her intentions were not to kill Sherlock.
As much as the scene is shocking, and disturbing, I specifically did not take my own personal feelings into any of my analyses. However I have been asked to do so in this case.
Being able to see that Mary never intended to kill Sherlock is important from a psychiatric perspective. Both Magnussen and Moriarty are classic and different examples of people with psychopathic personality disorder. Mary is not.
She makes a very good contrast to the two main villains of the series who are suffering psychiatric illness. Mary presents us with both a moral and ethical challenge.
In her love for John, we see a woman that we can related to and yet when she shoots Sherlock we see a killer.
The pivotal shooting scene shows us the two sides of Mary coming into conflict. She could have intentionally shot Sherlock somewhere more lethal but would still leave him alive for long enough to tie up John, but she didn't.
In less than a minute between Sherlock walking in and the shot, she had already made up her mind that she couldn't kill Sherlock. However she also could not afford to let him talk to John. In true Mary style she opted for the middle option.
As a very wise man once said: "The hottest place in Hell is reserved for those who remain neutral in times of great moral conflict".
Mary is definitely not morally neutral from our perspective but in her view she is choosing the "neutral" path. One that does not require her to compromise her security but would also limit damage to others.
Yes she could have talked to Sherlock, she could have trusted and she could have laid her secrets at her mercy. We know that he is a good man but she didn't. She didn't have the courage to place her trust in Sherlock, but she also didn't have the psychopathic ruthlessness to simply kill Sherlock to protect her secret.
Mary may not be a reformed character - but she is on the road to reformation and this is why I personally like her.
She is very flawed and very human. She shows us all that the road to redemption is rocky and littered with failure, but we can get there.
To Forgive is Divine.
Many readers have also asked why Sherlock forgave Mary so quickly. If we look at the two characters, they do share a great many similarities, or at least Mary and the old Sherlock did.
Although Sherlock was always on the side of the angels, he was never one of them. He has made several morally dubious choices that we have seen and most likely many more before he met John.
. I am sure he has done bad things for purely selfish reasons in the past in pursuit of solving a case. Sally is completely right when she said that Sherlock does not solve cases out of pure alturism, he does it because he gets an addictive high from them.
Sherlock understands what feels like to sacrifice your morals on the altar of necessity. He was just as flawed as Mary once, though we have never seen him shoot anyone.
Sherlock has almost completely his hero's path, but Mary has only just begun her journey. His empathy is one of a fellow traveller who understands all the pitfalls of the journey ahead.
Several commentors have pointed out that Mary doesn't look particularly pleased when she hears that Sherlock is alive but let us dissect this scene:
John tells Mary that Sherlock has pulled through, she is obviously smiling at this point. He then tells her that "Mary" was the first word out of Sherlock's mouth when he woke up. They proceed to hug, and Mary, out of sight of John, looks less happy.
Mary was surprised that Sherlock pulled through, not because she had intended to kill him but because she must have been updated by John about Sherlock's dire state. She must have then realised that her bullet wound was worse than she had planned and Sherlock could die, in fact he had cardiac arrest. That would be enough to worry Mary because now instead of simply incapacitating Sherlock, John views the shooting as murder (admittedly the attempted sort).
However she does not look very worried or perturbed by John's news that Sherlock has pulled through. She can now go back to her previous plan. She is more rattled by the fact that Sherlock had recovered his powers of speech enough already to say her name. John hasn't figured out the connection yet, but she is running out of time to put the rest of her plan into motion: intimidate Sherlock into keeping silent,
Mary is a master of the shadowy word of violence and intimidation, she is doing what she knows and what she does best. There was never any doubt in her mind that she could make Sherlock keep silent.
Mary must have planned to be there before Sherlock woke up from the anaesthesia/opioid painkillers the doctors would have unleashed on him. She could then wake him up (by turning down that morphine pump) when John was conveniently out of the room and start their conversation at a time to suit her. Mary would not have been happy when she found that she had timed her visit a little too late and that Sherlock was at least partially conscious.