This collection of information is taken mostly from brilliant others and very few of these theories are my own. Those of them that are I won’t say because they are probably wrong.
Section #1: The film evidence
Sherlock jumped off of a building. He had no pulse, there was blood all around his head, he was dead and buried. Except that he wasn’t. The moment viewers ceased watching the final episode of Sherlock Season 2, the questions and the speculation began. Throughout a slew of theories, facts and evidence I have picked my way through and pulled out what I believe to be of importance. I will present evidence from fans, hints and the actual film and give my own conclusive theory. However, no one will really know what happened until Sherlock himself reveals it. That’s the beauty of Sherlock Holmes.
Sherlock knows that he is going to die. However, he only knows it for about the last 20 minutes of the film, which means that anything before that it most likely irrelevant to the case. Collected in this section is the FACTUAL evidence from the episode and the theories to that support it. We will be starting with 3 characters - John, Molly, and Sherlock himself - and look at what they say and do that give us clues.
John Watson: John is Sherlock’s best (and only) friend. It seems natural that John would be in on the plan for whatever Sherlock does to survive. However, it is clear that John has no idea, is completely in the dark and that is how Sherlock wants it to be. It is John, though, that Sherlock calls, and this phone call cannot be disregarded as having hints about what will happen. See The Phonecall. Here we will be looking at what happens to John:
#1 Sherlock tells him a couple of times to stay where he is and to keep his eyes on Sherlock and Sherlock alone. Obviously John is wanted in a specific position - but why? It is enough to gather from the film that the place where John is positioned means that Sherlock’s point of impact is blocked by a building. The fact that John is told to watch Sherlock can also lead to the conclusion that something is happening on John’s eye level that Sherlock does not want him to see. What this is remains to be seen.
#2 When Sherlock falls, John rushes forward only to be knocked over by a cyclist. As seen in the film the biker is far enough away when John starts to easily avoid him, but John is bowled over and does not get up for several moments. This implies that not only did the biker purposely knock John over, but something happened that John was not able to see. It would also fuzzy the already traumatized John and make a sound medical analysis difficult.
Molly Hooper: Molly is naive, socially awkward and cute. However, she is clearly a smart young woman and she has helped in times past with Sherlock. Molly is quite obviously key in Sherlock’s survival suicide.
#1 Molly doesn’t count. She says so herself, and this simple phrase is Moriarty’s biggest mistake and Sherlock’s biggest triumph. Moriarty tells Sherlock that he has guns pointed at every single one of Sherlock’s friends - but not Molly. And Sherlock does not mention Molly’s name, although she obviously counts to him. He does not draw attention to the fact that Moriarty missed her. Sherlock’s visit to Molly tells her that, and he tells her, and no one else, that he feels that he is going to die. He also asks for her help, something he does to no one else. Molly is never mentioned again after that scene except in the phone call between John and Sherlock (see The Phonecall). In overlooking Molly, Moriarty’s schemes failed.
#2 Molly works at the mortuary. She is in constant contact with dead bodies and often let’s Sherlock examine them. It would be simple enough for Molly to provide a dead body for Sherlock’s burial, fake paperwork that said he dies, funky DNA (after all, Irene Adler said that all that counts is the DNA and she too faked her death) and also blood for the sidewalk and paramedics to carry Sherlock’s ‘dead’ body to safety. She could also have provided the serum that Irene Adler uses to fake her death, though this would discontinue The Rubber Ball Theory. Molly could have done numerous things to help him survive, and almost certainly had a hand in it. Molly sees more than other people, as she reveals to Sherlock in the lab scene, and it could be this reason and the fact that Sherlock knew Moriarty would overlook her that he chose Molly and no one else to help him.
Sherlock Holmes: He should have died, but he didn’t. Obviously Sherlock had a plan from the moment he figured out that he was going to die. It was in that moment that he knew Moriarty was going to have to play HIS game. Sherlock is obviously surprised by the things Moriarty knew that he didn’t. Moriarty is Sherlock’s obvious equal, since they both outsmarted the other. When Moriarty kills himself it complicates things, but only insofar as Sherlock believed he would be able to get out of this easy. Sherlock didn’t know how Moriarty was planning to destroy him, since he was surprised by the gunmen threatening his friends. The only reason Sherlock was upset was because he was going to have to lie to John and because there’s always the chance that your fake suicide might have a hitch and not turn out so fake after all.
#1 Sherlock chose the crime scene. He texted Moriarty where he wanted to meet. The meeting was therefore dictated on Sherlock’s terms and alludes to the fact that Sherlock wanted that specific place; perhaps because he already had something set up. Also, the building that he chose is very near to the mortuary; the place where Molly works. Obviously Sherlock knows what he’s doing and already has something set up there.
The Phone Call: This has significance, and there’s no point in denying it. Sherlock doesn’t want John to know that he is innocent - whether because he wants to protect John in case on the phone call being intercepted or afraid that John would blab. It does seem, however, that Sherlock gave him clues. Below is the phone call recorded in it’s entirety from the episode:
Watson: Sherlock, are you okay?
Holmes: Turn around and walk back the way you came.
Watson: No, I'm coming in.
Sherlock: Just. Do as I ask. Please.
Watson: Where?
Sherlock: Stop there.
Watson: Sherlock.
Sherlock: Okay, look up. I'm on the rooftop.
Watson: Oh god.
Sherlock: I— I— I can't come down so we'll just have to do it like this.
Watson: What's going on?
Sherlock: An apology. It's all true.
Watson: What?
Sherlock: Everything they said about me. I invented Moriarty.
Watson: Why are you saying this?
Sherlock: I'm a fake.
Watson: Sherlock—
Sherlock: The newspapers were right all along. I want you to tell Lestrade, I want you to tell Mrs. Hudson and Molly. In fact, tell anyone who will listen to you. That I created Moriarty for my own purposes.
Watson: Okay, shut up, Sherlock. Shut up. The first time we met—the first time we met—you knew all about my sister, right?
Sherlock: Nobody could be that clever.
Watson: You could.
Sherlock: I researched you. Before we met I discovered everything that I could to impress you. It's a trick. Its just a magic trick.
Watson: No. Alright, stop it now.
Sherlock: No, stay exactly where you are. Don't move.
Watson: Alright.
Sherlock: Keep your eyes fixed on me. Please, will you do this for me?
Watson: Do what?
Holmes: This phone call, it's... it's my note. That's what people do, don't they? Leave a note.
Watson: Leave a note when?
Sherlock: Goodbye, John.
Starting from the beginning, John is told to stay where he is. We have been over this section before. When Sherlock begins to apologize is where it gets strange. Sherlock doesn’t apologize. Clearly this is a strenuating circumstance. While I have already said that he could be doing this to protect John and keep him in the dark, this could also be a clue that he is faking his death. He tells John flat out “I’m a fake” before going on to explain that he is a fake for the newspapers (he also mentions Molly here - perhaps to make John unsuspicious that Molly actually is in cahoots with him). When John mentions that he knew about his sister in their first meeting, Sherlock hesitates before answering “I researched you”. It is a lame answer and John should know it - Sherlock had never even heard his name mentioned before, as the man who introduced the two had also just met John that morning and immediately took John to Sherlock. Sherlock would have had exactly no time to research John. Obviously Sherlock was lying and John probably should have caught that.
The key in this phone conversation is a phrase Sherlock repeats twice in a row: “It’s a trick. It’s just a magic trick.” Notice that he is not speaking in the past tense here, as he was in his previous statement, so it is likely that he is not referring to looking John up at all. There are a couple of theories for this, both The Rubber Ball Theory and simply the fact that he is telling John, clearly and plainly, that all is not what it seems.
The Rubber Ball Theory: Perhaps one of the most ingenious speculations is that of the rubber ball. In the two scenes directly before Sherlock goes to the hospital roof, he is playing with a small, black rubber ball. This is seemingly unimportant but the fact remains that Sherlock has never before played with a ball while he is thinking. Is this small sphere of rubber important?
There is an old magic trick where, if you put something small, round and hard in your elbow and squeeze, it will slow down your pulse on that arm until it is nearly undetectable. Sherlock could be referring to this when he tells John “It’s a magic trick”.
When Sherlock’s body is on the pavement, one of the people in the surrounding crowd is kneeling on his left side and holding his left arm. What random passerby would want to hold onto the arm of a man who recently committed suicide? Unless it wasn’t a random passerby after all - the fact that they were holding that arm made John unable to check the pulse of it, and he had to check the other one - assumedly the one that had the ball in the elbow.
The Crime Scene: It is the scene of the Reichenbach Fall that has sprung the most theories. How Sherlock landed, if he jumped at all, if there was a twin of him, etc. In this section, however, I will discuss only the setup as seen in the film exactly, not how I think he actually did it. I will set it up the way that it is seen in the episode, no more.
The hospital is several stories high. Sherlock is standing at the top of it. In a shot where he looks down, we see a sidewalk with people on it, a laundry truck parked in front of it, and behind the laundry truck a large chalk square. John’s view is blocked by another building, which means there is something between the the jump and the impact that he doesn’t see. Even the cinematography cuts out a part between the fall and the actual impact. Sherlock jumps vertically but is sideways when shown. He is lying outside of the chalk square, and people crowd around him. There is a lot of blood on both sides of his head. People hold John back for a while before he can actually get to the body though everyone else seems to be let through fine.
This concludes the evidence in the film.
Section #2: The Hints
Moffat and his co-workers have dropped hints here and there as to how it happened - nothing big and definitely nothing substantial, but hints nonetheless.
Moffat said in an interview that there was clue “everyone had missed”. There has been unending speculation about this, but no one will ever know until Moffat decides to reveal it. The most popular theory, however, has been that of the rubber ball, explained above.
Moffat did give some more substantial hints in another interview, though, saying things such as “He’s got to interrupt the fall before he hits the pavement, really.” He also says that there is a clue hidden in something “rather uncharacteristic of Sherlock”.
At the San Diego Comic-Con, another clue was learned: That Sherlock’s survival could be figured out from footage in Season 2.
And finally, a photo from season two reveals Sherlock falling by a window...that has Molly looking out of it. Implications, implications...
Section #3: The Speculations, theories, and all that beautiful Mess
Well unlike Moffat I don’t have time to look through every theory posted online, but I have taken the liberty of pulling out the ones I found interesting, valid or simply odd. It is mostly a collection of facts and thoughts pulled from research. I have categories and specific theories in each category:
THE LANDING THEORIES
The Laundry Truck: This is a big one - that Sherlock jumped into the laundry truck, climbed out and had some blood splashed around. The truck drives away, notice, soon after impact. You’d think the driver would stay around if a man died right next to his bus window!
The Pink Suitcase: This one intrigued me very much. As in the first episode, where Sherlock knew there was a suitcase by the fact that it was missing, speculation has been that because there was a laundry truck it must have been picking up laundry, and it was into this that Sherlock jumped. However, due to the fact that we see the impact and that there was no laundry when Sherlock looked down, I tend to find this theory a bit weak.
The Chalk Outline: Sherlock could have had someone remove the cement blocks and replace them with something softer. (Let’s remember, though, that Sherlock landed outside the outline).
The Legs: Sherlock flaps his legs as he falls. Apparently scientists say that since bending the legs reduces an impact then he could have survived. Doesn’t explain the blood and no pulse, though.
THE BODY THEORIES
The Moriarty Fall: Moriarty in Sherlock’s clothes fell. Yeah...no.
The Body Switcheroo: Slightly more plausible than the above. Sherlock fell (somewhere soft) and Molly found a new body that looked like him somewhere in the mortuary and doused it with blood.
The Kidnapper: Probably having the most evidence to back it, this theory takes on the fact that the screaming governor's daughter is never fully explained. Perhaps a kidnapper who looks a heck of a lot like Sherlock is walking around town, and it was he who fell from the roof, not Sherlock. Except no one else was up there.
The Hanged Dummy: In the beginning we see a dummy hung by it’s neck in Sherlock’s room. Perhaps this was used?
Cloning: In “Hounds of Baskerville” Sherlock mentions human cloning. Well, Moffat did say it would all be in Season 2, not just the last episode...
OTHER THEORIES
The Hallucinative Fear Gas: The cyclist might have sprayed this gas on John when they bumped, making John think Sherlock was dead.
Mycroft Helped Him: His well connected brother could probably easily stage a death, but it is unlikely that Sherlock went to him for help.
Super Sherlock: Sherlock went for a ride with Dr. Who and came back as an alien with regenerative powers. Surprisingly, there is absolutely nothing to support this theory...
Bad Memory: Drugged by the fear gas (which thrives on fear and stimulus, and seeing WHAT YOU EXPECT TO SEE), John is recounting what happened to his therapist. Bad memory, perhaps? Sherlock himself has a slight memory lapse in the same episode (perhaps this is what is ‘uncharacteristic’ of him?), and John could be suffering from both. Sherlock never jumped at all.
Reichenbach Fall: Since it isn’t called SHERLOCK’S Fall, Moriarty was the one who fell, and he apparently conveniently looks like Sherlock. I guess people forget that it is named that because the original story is called “The Reichenbach Falls”. (Like “Hounds of Baskerville” is named after “The Hound of the Baskervilles”).
Rapall: Since Sherlock “uncharacteristically” told Kitty Riley “You repel me” (he doesn’t usually form such staunch opinions of people so fast, if ever), it could be a clue that he used rapall, lowering himself down slowly enough and breaking his fall before leaping lightly to the ground and dousing himself with blood.
MY OWN THEORY
Sherlock asked Molly for
a. A fake death certificate
b. Fake blood
c. Another body to bury
Sherlock is on the building. I personally think that it was Sherlock who jumped and Sherlock who landed. HOWEVER I think that due to the wrong angle of the body and a the picture released from season 3, he (waving his legs to break the fall) landed on a platform directly behind the building and about halfway down so that John (who he had told to stay and was then knocked over by the bike) could not see. He then jumped from there and landed on the cement. However this is still probably enough to stun him, which explains why he could lie so still with his eyes so open. It is clearly Sherlock on the ground. I do not think that he jumped into the laundry truck, but I think that there was fake blood somewhere in the truck that was quickly doused onto Sherlock - as it is on both sides of his face and not just his right (where he supposedly landed) it is clear that it is fake. John, hurrying to his friend, is held back for a while. The passerbyes seem upset but not terrified. They were probably expecting this, because Sherlock told them to be there.
Now for the pulse. I do not know for sure whether Molly gave him the drug Irene used or not, but I am inclined to think that it is the rubber ball that was used to stop the pulse. This would also explain Sherlock doing his “uncharacteristic” thing - crying and apologizing to John - while telling him about the ‘magic trick’. Moffat will not have wanted to just reuse the drug, it would be too easy.
John, already terrified, stressed, and fuzzy from being knocked down by the cyclist, would be unable to function well, and Molly sent paramedics (who got there conveniently fast for the suicide having just happened, and no one called them; you can see that none of the passerbyes (AKA the homeless network) are talking on phones like they are calling an ambulance) to get him out of there before John could give him a deeper analysis. Molly provided a body for the funeral (who knows, maybe the kidnapper who supposedly looks like Sherlock?) and fake death papers. Who knows where Sherlock is hiding now?
