[This article contains MASSIVE SPOILERS for Star Wars: Episode 7 - The Force Awakens]
Now that fans chomping at the bit to see what story J.J. Abrams and the new Lucasfilm have in mind for Star Wars: Episode VII: The Force Awakens, the biggest surprise has been let out of the bag: it's Rey (Daisy Ridley) who holds the key to victory over the darkness. But the metheod through which she came to realize it (or was forced to) wasn't exactly clear for every viewer.
In a movie filled with subtle references to previous Star Wars stories, the jumble of images and narration may have seemed intentionally confusing. But dissecting Rey's Force Vision/flashback - or 'Force-back,' as it's being called by producers - actually makes several subplots and story threads clear. At least, as clear as they can be so early in the next chapter of the saga. But there's more than enough to break down for hardcore fans and casual moviegoers alike.
So for those who couldn't keep up with the images, scenes, or lines of dialogue being spoken as Rey took her "first steps into a larger world," allow us to explain.
The Skywalker Legacy
To be clear, the vision is triggered when Rey first places her hands on the lightsaber which "belonged to Luke Skywalker." It's this (blue) saber which Obi-Wan first delivers to Luke on Tatooine, having been used by Anakin Skywalker up until the moment he was de-limbed and left for dead by Obi-Wan. Luke wielded the saber in A New Hope and The Empire Strikes Back, until it was sliced from his hand (along with his hand from his arm) and sent tumbling into the depths of Cloud City.
That fight sequence should be at the forefront of fan memory, since the first hint we get that Rey has stumbled into a vision is her location. Suddenly kneeling in the middle of a dark hallway, as the sound of a lightsaber - Darth Vader's - ignites, and the hallway is lit one light at a time. The hallway is the one seen above, acting as a backdrop to Luke and Vader's saber battle in Empire, leading up to the latter's reveal that he is a Skywalker himself.
Right off the bat, it's made perfectly clear that Luke's lightsaber (and Anakin's before it) enjoys a unique link to the past of both men. Specifically, the last time it was wielded by any Jedi (as far as we know). But the Cloud City corridor is just the first hint we get that the saber forged by Anakin still possesses a link to his line.
The next image of Luke would be difficult to make out, if not for the all-too-familiar droid alongside him. That's Luke's robotic hand clutching R2-D2's 'skull' while he speaks some indiscernible lines of dialogue. Given the gravity of the scene, most have assumed that this scene is set just before Luke's self-imposed exile, sending R2 back into Resistance hands and hiding from those around him (with a map to find him).
We say "assumed" because there's no actual evidence in The Force Awakens that this scene is set in the past, prior to Luke's exile. R2-D2 appears just as burnt, banged up and rusted as he does when BB-8 discovers him at the Resistance's base - but was nearly spotless at the end of Return of The Jedi. Which leaves two conclusions: either Luke let his beloved droid fall completely into disrepair following the fall of the Empire, or the damage is a result of sitting in storage - which would suggest this scene may not yet have happened.
How would the saber carry this memory anyway? If it hasn't been wielded by Luke since Empire, then the flashback of his time with the weapons should have ended there. The alternative is that the lightsaber can grant its wielder visions of its own past and future, once again implying that the scene above will happen. We'll be coming back to this point later.
That's just speculation and fuel for discussion, but the biggest point to take away from the scene is that, whether it's a product of the Force or just the Skywalker saber, the weapon carries important moments of the wielder's past and future. Should a Force user like Rey touch it, the Force delivers a crash course in the weapon's history. A nifty trick.