Elena is Katherine.Elena looks exactly like an immortal vampire from the 1860s, and survived a car crash that killed both her parents. The simplest explanation is that she actually is the vampire, and "Elena" is just her cover identity. As for the sun, maybe she just has an earring that protects her.
Lexi is an Original.Because:
The First Woman is Klausís mother and the First Doppelganger is his sister.Klausís mother was a witch who became a vampire by drinking babyís blood. She was a lamia, a vampire who could have babies and she turned Klausís father into a vampire as well. Her daughter was a doppelganger because she was a girl. Klausís sister had a baby with a human and that diluted the lamia blood, so the next doppelganger turned up some generations after, increasing in generational span until Katherine, and then Elena.
The "ghosts" are in fact the First Evil.They share the exact same attributes as the First - incorporeal, can only appear as dead people. In 3x06 Vicki attempted to become corporeal, the First's exact plan in Buffy. Vicki's plan seemed oddly OOC, far more on the evil side of the spectrum that alive!Vicki was. Explanation: it's not Vicki, it's the First Evil playing on Matt's insecurities.
Tyler or Caroline will die in the Season 3 finaleNow that they have set up a very good reason why one or both of them would betray the others and save Klaus one of them has to go. Either Caroline simply because Klaus get bored of her saying now triggering Tyler to want his vengence no matter the cost or Tyler because Klaus doesn't like competition. Either way unless some third option presents itself one of those two isn't long for this world.
Bonnie's Dad is whiteKaterina Graham is half black and he's not a warlock and we've never seen him
Shane killed his own wife and child to complete the first dozen sacrifice to bring Silas backHe mentions in an earlier episode that his wife and son were killed a while ago. And in episode ten, he fervently says that when Silas is raised, he will "bring back everyone" who died for him to be released. The only way he can be so sure about his family coming back to life is if he arranged their deaths to begin with.
Elijah is the unknown competitor in the race for the cureHe's been missing since the start of the season, and while he can't stand to be near his siblings (according to Kol), that doesn't mean he's not been keeping an eye on them. Subsequently, he notices Klaus' activities in Europe, learns that he dug up the Hunter's Sword and realized that Klaus is searching for the cure. It doesn't take long for him to discover that the recently turned Elena is the reason, so now he wants the cure strictly so Klaus doesn't make any more hybrids that will pose a threat to the vampire race. Either that or he's got a witch who can replicate Esther's binding spell, so that when he finds the cure he'll use it on himself, thereby curing the rest of his siblings and giving them back their humanity (even though that begs the question of how he got Elena's human blood to begin with). Plus, we've seen every other Original on the show now, each with their own reason for wanting the cure. It's strange that Elijah - the one who always has his own agenda/code - wouldn't participate.
In order to defeat Klaus...Elena and co. will revive all of the Original family. Elena will obviously try to rescue Stefan, and will realize that she doesn't have the firepower to even hope to touch Klaus. So she will track down Elijah (probably using Bonnie's tracking spell - remember Bonnie needed Elena's brother's blood to find her, and now they have Klaus' (Elijah's brother) blood). Elijah is buried along with the rest of his family, so when he wakes up he will then revive all his brothers and sister. Cue 6-on-1 Orginal-Vampire sneak attack.
Jeremy will end up taking the place of one of the Five.Since only potential vampire hunters and/or hunters can see the supernatural tattoo on Connor's arm, chances are that something will happen to one of these hunters, and Jeremy will end up taking his/her place and end up as a reluctant Dragon to season 4's Big Bad
Elena's blood issues are temporaryKatherine has been shown not drinking from the vein and has had no problems.
Jeremy is going to kill one of the OriginalsShane told Bonnie when Jeremy completes his Hunter's mark, that she'll need his help. Why is he so confident that Jeremy - the newbie Hunter - will be the first to have a full tattoo? It's because Shane knows that once you kill an Original vampire, every vampire that shares their bloodline will die. Tens of thousands of vampires dying all at once from killing just one vampire is a pretty efficient way to get that tattoo completed. Shane probably has a white-oak stake somewhere, or one of the swords the original Five used, and he'll make sure it finds its way into Jeremy's hands so he can use it to kill whichever Original is coming back to Mystic Falls. My money's on Kol, since he hasn't really gotten any character development beyond 'the crazy one.' Plus, he and Jeremy have prior history together. It would make sense for Jeremy to be the one to kill him.
Bonnie will become either the Dragon/Big Bad (at worst) or a Well-Intentioned Extremist at bestShe's tapped into serious dark magic to immobilize Klaus, and as of the third season finale, she helped him possess Tyler when Alaric staked his body. When Tyler!Klaus asks her why, she bluntly tells him that she did it to save her friends, and that she's "done letting all of you push [me] around." In the next season, she'll probably develop an addiction to dark magic.
Silas was in love with the Original DoppelgangerKlaus and Elijah was in love with Tatia (who came before Katherine). Stefan and Damon were in love with Katherine, and later Elena. Like Rebekah says Elena being on the island doesn't serve much purpose (even from a writers standpoint). Silas wakes up, mistakes Elena for the girl he loved... would give her a bigger purpose on the island.
Unjossed and Unconfirmed
Matt is doomed.The show doesn't hesitate to kill of supporting cast members and likes a body count for finales. Matt thinks that Caroline killed his sister, which makes him rife for being used by any number of villians, and he doesn't serve much of a role on the show other than being Caroline's love interest. He's got Alas, Poor Scrappy written all over him.
Alternately, Bonnie is doomed.The show has gone two seasons and failed to do anything with Bonnie. Matt could at least fill a Xander-esque role as the only real Normal on the show and now that his sister is back, he will probably get some more interesting storylines. While Bonnie on the other hand has even less of a character than Matt, and it seems like she will be sidelined in her own romance storyline what with the return of Anna and Vicki. Plus, her new powers have made her Too Useful To Use, as she is basically a walking Deus ex Machina now and so the show runs the risk of relying on her too much to easily solve plots. Alas, Poor Scrappy is more or less the only option left for her. Either way, the show is bound to kill off another main character sooner or later, and Matt and Bonnie seem to be the most likely candidates.
Elena will end up with an Third Option Love Interest.Just to make the shippers squirm.
Caroline will develop feelings for Klaus.It's as simple as that. When Tyler is revealed as still being alive he'll either come up with an explanation. Either the hybrids simply survived because they weren't vampires, and thus weren't subject to the same rules for some arbitrary reason or he'll reveal that Klaus somehow survived. From there it just writes itself until the truth one way or another comes out.
Katherine will be the one to help Elena transitionStefan is still not so good around human blood, and Damon makes a poor mentor. The originals will probably be leaving town, and Caroline is dealing with her own problems. Katherine will swoop in and help her transition into a vampire — not without an ulterior motive of course. She'll earn points with Stefan, and it never hurts to have another Vampire that looks exactly like you when you have as many enemies as Katherine has.
Klaus is The Great GatsbyThink about it - he was alive in the 20s, is fabulously wealthy but with a Dark and Troubled Past. He didn't actually die at the end of the novel, he just faked his own death because his father was onto him. And Klaus is certainly into making big romantic gestures and wearing smart suits. That's why he's so attracted to Caroline - she reminds him of Daisy, but is also caring and strong (unlike Daisy).
Klaus is responsible for creating Dracula.Klaus has fought in every war since the battle's of Alexander the Great. In the fourteen hundreds he fought in the same war as Vlad Dracula in his human life. Klaus and Dracula heard of eachother and met either on the battlefield. Wanting what Klaus had, Vlad either had Klaus bite him or met a witch who was willing to turn him into a vampire like Esther did to Klaus.
Katherine Pierce is an ancestor of Selina Kyle.They both like to dress dark and seductive. They are both better people than they seem, but have to look out for themselves.
Pastor Young blew up the council to summon Connor.
Atticus Shane needs the Five to kill vampires, and use their completed mark to find and free Silas, the REAL OriginalWhen a Hunter completes his mark, the resulting map leads to the actual resting place of Silas, who is - according to Shane's presentation of foreshadowing - the real first vampire to exist, but was sealed by Ketsia before he could change anyone else. The so-called 'cure' (and also 'weapon,' if Klaus is to be believed) is Silas himself: an insanely powerful vampire predating the Mikaelsons, whose goal will be to rid the world of the so-called Originals, killing every other existing vampire/hybrid as well, and then restarting the vampire race from his own blood. The reason Shane's been pushing Bonnie to perform magic is so she can be powerful enough to break the seal on Silas' grave. Not only that, but by tapping into dark magic to try and rescue Elena in the fourth season premiere, she set off the chain of events that will lead to Silas' return. The reason Shane would unleash an all-powerful crazy-evil vampire on the world is because the true purpose of the Five is to let Silas do his dirty work, and then kill him before he can make new vampires. He's keeping this to himself is because he knows the Hunters won't kill vampires if it means the end result is unleashing an evil that will kill innocents as well as vampires.
April Young is the cureSince coming to Mystic Falls, she hasn't really done anything. She is a literal MacGuffin that's sitting right under the protagonists' noses. And like the Doppleganger, it's her blood that's the cure. The only problem is that if a vampire wants to be cured, they have to drain every single last drop of it, which will be a problem for Elena once she finds out.
Professor Shane is SilasMaking him immortal. He seems to know everything and living a long life is a good to do that.
Physical attractiveness is supernatural baitThe main cast are all rather good looking, which given the weird things that happens to them all, clearly physical good looks are a curse in the TVD universe. Vampires, werewolves, witches, hybrids, you-name-its never bother the ordinary looking residents of Mystic Falls.
Katherine will try to kill Elena to save herself from KlausKatherine's main motivation is clearly her own survival - she's ruthless about it, and will do anything to keep herself alive. Klaus has it in for her, since she delayed his plans to become The Hybrid by 500 years by turning herself into a vampire and depriving him of her doppelganger blood. Klaus need's Elena's doppelganger blood to create more hybrids, which he is obsessed with doing. He is therefore obsessed with keeping Elena alive long enough to find the supposed cure for vampirism, so that he can turn her human again and use her blood to make more hybrids. If Katherine finds out about the cure, she will try to kill Elena to make herself the only existing doppelganger, so that Klaus will be forced to keep her alive/not kill her if he wants to ever make more hybirds.
Sage was sired to Finn
Stefan is going to double-cross RebekahRebekah now wants the cure to ram it down Klaus' throat and turn him human again. But who's to say that Klaus won't immediately die as rapid aging descends on him? Or if that doesn't happen, at best he'll only be alive for another fifty to sixty years. Either way, once he dies, so do all the vampires who share his bloodline, which includes Stefan himself, Damon, Caroline, Tyler and Elena. Stefan will deceive Rebekah in some way, and keep the cure for whatever he wants to use it for.
Silas and the cure are one and the sameSilas' power is to 'bring back the dead.' Vampires are basically undead. If Revive Kills Zombie applies in this universe, Silas' power will be like pouring a Phoenix Down on a ghoul re: vampires.
The cure will be used to defeat SilasBut won't be used by any of the characters
Caroline was playing KlausThink about it. She was dying from a werewolf bite - one he inflicted on her, no less - and the only way to save her was by drinking his blood. Plus, Tyler would never leave Caroline alone with Klaus, much less when she's dying. They planned it together and placed their bets on Klaus' feelings for Caroline to make him do the right thing. She sees something human in Klaus, sure, but ultimately she was just saying what she thought to save her life.
Bonnie is descended from Qetsiyah and SilasQetsiyah didn't know she was pregnant until after she already sealed Silas away. It's why the spell to release Silas calls for a Bennett witch, as they're part of his line. It's also why the Bennett family of witches are highly regarded in the supernatural world: their ultimate ancestors are the world's first immortal being and the witch who was powerful enough to even grant the spell.
Katherine wants the cure as a bargaining chipShe doesn't seem to miss being human all that much. My guess is, she'll use it to either a) force-feed it to Klaus and kill him, freeing her from his vengeance forever or b) use it to keep Silas in check. Katherine's too smart to risk the end of the world unless she had a back-up plan to make sure Silas doesn't turn on her.
The tombstone is part of a back-up to stop Silas if the cure is stolen or destroyedIt contains the calcified blood of Qetsiyah. If anything happens to the cure and Silas goes free, it's going to be the critical piece in stopping him, but at a great price.
Tyler is dead. Klaus caught up with him, and he's been listening to Caroline's voicemails
Shane isn't deadWhen Rebekah found him, he was just barely alive. She used her blood to heal him (assuming vampire blood can cure extreme blood loss), and now she has him in her pocket for whatever plan she has for Silas and the cure. We only have her word that he died on the island, after all.
Hayley and her family are Klaus' secret weapons against SilasIt'll tie up her character arc more neatly than just having her be used as a pawn by Silas and Katherine and then disappearing off the face of the earth. Since they're an ancient family of werewolves, chances are that they know of Silas and can be effective against him. So if Silas ever brings the other side, Klaus has a werewolf army to put between him and Silas and every other vampire that he's killed.
Silas is being haunted by JeremyHe keeps talking about how he wants the cure so he can die. Jeremy is telling him he needs to die.
Silas has/had a brother.And Damon is his Doppelganger.
Anna stopped Mikael's heart
Megan has a Gilbert ring
Amara is still aliveIf she was truly dead, nature wouldn't have kept the Petrova doppelganger line going like it did with the Salvatore line. Once Qetsiyah killed her, a part of her consciousness remained in that tiny tube filled with her blood. And now that Katherine's taken the cure and has her ancestor's blood coursing through her veins, Amara is slowly being reborn through her, so she can finally give Silas the peace and salvation he needs.
Katherine's going to embrace vampirism againBeing a vampire gave her benefits to add to her cunning, so naturally she wants to be strong. Then there's the fact that her daughter is a vampire as well, and they do have five hundred years to catch up on. Katherine will become a vampire again so she can spend eternity with Nadia.
Katherine's illness is a bad case of advanced agingOnce a vampire being takes the cure, they become human...and then slowly begin to feel the weight of all the years they "lived". Their teeth fall out, their hair becomes gray and then eventually they simply turn to dust. That's what's going on with Katherine (and presumably Silas, unless the cure effects him and Amara differently).
The Initiative is Alive and WellWhat, you didn't think that just because Buffy beat them and their Frankenstein monster they would just stop trying to make better monsters did you?