A long time ago, on a distant planet called Gallifrey, there was a man who was known as the Doctor. He was studying to become a Time Lord; one who helped to keep the laws of time under control. But after a while, he became tired of his boring studies. Instead of continuing on, he finished the rest of his studies in one semester, being a very smart man. Once he had completed them, he decided to do something a bit more exciting. So he went to a museum close to where he lived. In the museum, there was a ship they had on display. The moment he touched the console, he knew that it was the most beautiful thing he'd ever seen. So, after everyone had gone, he crept into the TARDIS. TARDIS, T-A-R-D-I-S, stands for Time and Relative Dimensions in Space. It goes anywhere in time and space, and is the most infinite ship in the world. The Doctor went into that TARDIS, and flew it right out of the museum. He ran far away from Gallifrey, and didn't return for quite some time. But then it came. The great Time War. So many different species, fighting for the rights to time. Everyone was losing, and there was nothing they could do. But then then The Doctor returned. He knew what he had to do. It was a terrible thing, but it had to be done. He went to Gallifrey, and he burned it. The whole planet went up in flames, and all the people with it. Except for the Doctor. He lived on, and in misery, too. The thought of his burned planet weighed down on his shoulders for years. So he took that TARDIS and he ran away again. He's been running ever since.
Quite a few years later, in London, England, the most remarkable human being on the planet was born. His name was Sherlock Holmes. He could calculate anything he wanted to, and simply by looking at a man's coat, could determine who he was married to, where he worked, and why he had been to the pub the night before. Him and his brother, Mycroft, grew up as enemies, disliking each other quite a bit. Then, as an adult, Sherlock met Doctor John Watson, an army veteran from the Vietnam war. Together, they solved mysteries, and still are doing so right now.
Around the same time Sherlock was born, two brothers were born as well. In Lawrence, Kansas, Sam and Dean Winchester grew up- for only about 4 years, before their mother died due to a demon attack on Sam. Only six months old, Sam had an unexpected visit from the demon Azazel; who, when interrupted by Mary Winchester, murdered her, burning down their house and causing a deep, burning craving for revenge in John, their father. Ever since then, John Winchester hunted demons, spirits, and all other evil, supernatural things. His sons, Sam and Dean, also carried out his legacy after his death, also due to the demon Azazel. After a four month trip to hell due to hellhounds released by the first demon created, Lilith, Dean arose from his grave, completely clueless as to how he got out. That's when met up with the celestial being, Castiel. Dean then discovered that it was Castiel who saved him from hell. However, problems were arising with his brother, Sam, who fell for the lies and deceit of the demon Ruby, who helped them with many things, but in the process ended getting Sam addicted to the blood she produced. This gave Sam great power, enough to destroy demons with his mind. Unfortunately, when he destroyed Lilith, he broke the last of the 66 seals and released Lucifer from his cage. This then became an even bigger problem because Sam discovered he was Lucifer's vessel, or the person Lucifer would take over the body of. To add to the problem, Dean discovered he was the angel Michael's vessel. But discovering they had another brother, Adam, Micheal instead raised him from the dead to use him as a vessel. Sam then agreed to being Lucifer's vessel, and proceeded to create a doorway to his cage, using the rings of four horseman. War, Famine, The False Prophet, and Death Himself. Once the door was open, Sam jumped in, dragging Michael and Lucifer with him. He was there for one year, although, to him it felt like 120 years. When he was rescued, unfortunately, his soul did not make the return trip. So, Sam's soulless body hunted demons for another year, with his risen grandfather, Samuel. When Dean discovered that his soul was missing, he called to Death for help. Death explained to him that Sam's soul would be so tortured by being stuck in the cage with Lucifer and Michael, that the traumatization would probably kill him. Still not giving up hope, Dean insisted that there must be something Death could do. Death told him he could put up a wall in Sam's soul that blocked the memories from hell out. Unfortunately, Castiel betrayed them by teaming up with the demon Crowley to open Purgatory, the hell for monsters. In doing this, he broke the wall in Sam's mind and Sam saw Lucifer everywhere he went. He ended up in a psychiatric ward. The Leviathan were released, and they killed Castiel. Desperate to find a way to heal Sam, Dean found a healer named Emanuel, who turned out to be Castiel, with of course no memory of who he was. But, it all came to him when he killed a couple of demons in order to rescue Sam. Then, in order to heal Sam he had to shift the insanity over to himself,which in the process put him in a coma. The demon Meg, on their side, took care of him until he woke up, and when he did, he was definitely still not right in the head. When the leader of the Leviathan, Dick Roman, had been killed, Dean and Castiel had been sent to Purgatory with him. Dean found a way out by finding a tear in Purgatory that only humans could get out of, intending to bring Castiel with him. Unfortunately, Castiel stayed behind, thinking Purgatory a punishment for what he had done. A few months after Dean got out, as he was washing his face, Castiel appeared behind him. He had gotten out of Purgatory, but he had no idea how. That's when the angel Naomi was trying to control the mind of him and many other angels. Metatron, the one who wrote the word of God in which the prophet Kevin Tran (advanced placement), could translate, was one of the few angels who were not working for Naomi. Unfortunately, he had other plans, and he ended up tricking Castiel into letting him into Heaven to take over. He then ripped the grace out of all the angels, and just as Sam was about to cure Crowley, all the angels fell from heaven at once. All angels human, Dean, Sam, and Castiel had no idea what to do.