Forget all your theories about R + L = J, this post is all about the one and only Hodor.
As we found out in previous episodes when Bran and the Three-Eyed Raven traveled back in time, Hodor's real name is Wylis and he was a stable boy for the Starks at Winterfell.
However, Bran got a little overzealous with his time-traveling abilities in last night's episode called "The Door" and he messed up in a major way. This had disastrous results for Hodor.
While the Three-Eyed Raven was sleeping, Bran decided to do a little time traveling on his own and wandered upon an army of White Walkers and their leader, the Night's King.
When Bran turns around, the Night's King is standing right behind him, and is actually able to reach out and touch his arm, leaving his mark.
When Bran wakes, he is told that they are no longer protected in their cave with the weirwood tree and the White Walkers can now get in. Oh yeah, they are currently on the way, as well!
It should be noted — we found out earlier in the episode — that the Children of the Forest actually created the White Walkers thousands of years ago when they were fighting humans and the Walkers now seem to be on a mission of revenge against them.
With little time to spare, the Three-Eyed Raven and Bran time travel one last time as the White Walkers are on the way. Little do they know they are already at the front door and all hell breaks loose. Damn, zombies move quick.
They naturally get into the cave and start wreaking havoc everywhere.
Bran's direwolf Summer sacrifices himself (stop killing the wolves, Game of Thrones!), as do a number of the Children of the Forest, so the young Stark can escape.
Sadly, they do not have enough time to get away as they are being overrun, and Bran just won't wake up. So Meera grabs a sled, throws Bran on top and starts pulling him away. As she exits the cave with the White Walkers right behind them, she yells to Hodor "Hold the door!"
Since Bran was time traveling, he accidentally seems to warg into Wylis in his vision while Meera is screaming at him. Wylis begins to have a seizure and begins saying over and over again "hold the door," which eventually shortens to ... Hodor.
As The Verge elegantly states, "As a boy he was incepted with a single-minded drive to one day hold a door so that a little magic boy could escape some zombies. Hodor isn't an ancient sacred name or a link back to his giant heritage, it's the name of his chief function in life."
Well, OK, not elegant, but to the point.
So, yeah, not only is Hodor Hodor because of Bran, Hodor is no more ... also because of Bran. Damnit, Bran.
After the episode, the two actors talked with HBO about Hodor's untimely death and ultimate sacrifice.
Kristian Nairn said it was initially a "difficult scene to read," because he loved the character to death. He was, however, happy with the way Hodor went out.
Isaac Hempstead-Wright said it was "mortifying," because Hodor didn't have an "agenda of any kind." He was just a kind character who didn't deserve it.