This is from Badass Digest, a site that has been super reliable in the past. If you don’t want to risk a possible spoiler, stop reading. However, if you want to see the pretty ingenious way Episode VII might tie directly to Empire Strikes Back, keep reading.

From Badass Digest:
Imagine the standard Star Wars crawl, and when it ends the camera pans up to the stars. But instead of a spaceship zooming into frame we see… a hand! A severed hand, tumbling through space. A severed hand gripping a light saber.
That hand falls onto a desert planet, where it is discovered by characters who will be our heroes. One is Daisy Ridley. The other is John Boyega, who is playing someone trying to change his path in life (again, I’m keeping it vague here). They recognize the light saber as a Jedi relic and decide to return it to the proper people.
Their quest takes them off world, and they meet up with Han Solo and Chewbacca, who aren’t flying around in the Millenium Falcon anymore but are piloting… well, that could be a spoiler. I’ll leave it. Anyway, Han and Chewie recognize the light saber as Luke’s, and they say they haven’t seen their friend in thirty years, since the events of Return of the Jedi.
So begins a quest to find the missing Jedi Master. Meanwhile, on an ice planet, nefarious forces are building a super weapon, one capable of destroying not planets but entire solar systems…
In many ways this plot of Episode VII is an echo of A New Hope. Instead of R2 coming to Tatooine it’s a hand falling from the sky, but the basic sweep of the story is similar, and intentionally so. But things that seem familiar may not be as familiar as you think – don’t assume that every ice or desert planet in the galaxy has already been visited, if you know what I’m saying.