Everyone who has read or watched Harry Potter and the Goblet of Fire will know how it ends.
It's traumatic AF with Cedric dying and all...
However, Tumblr user Miraniel has noticed something fishy about the Triwizard Cup/portkey that could have led to a very dark plot line.
Harry and Cedric grab the cup that teleports them to the graveyard. Usually with portkeys, they only travel one way. This one went two ways.
The portkey also travels to the front of the maze, not the middle... where it was originally.
The theory suggests that a Death Eater, or Voldemort himself, was going to travel back to Hogwarts using the portkey after he killed Harry, and join Barty Crouch Jr. as an undercover agent.
Who would he be? Harry, duh!
With Harry dead, Voldemort would have a whole head of his hair to create Polyjuice potion with. All he would have to do is pretend to be Harry long enough to get close to Dumbledore, easily killing him and becoming the master of the Elder Wand.