[Almost] always generating new spoilers! As seen on xkcd.com/2243/
In this Star Wars movie, our heroes return to take on the First Order and new villain:
Darth Sebelius with help from their new friend Teen Yoda, Rey builds a new Lightsaber with a beige blade and they head out to confront the First Order's new superweapon, The Planet Zester a space station capable of triggering the end credits before the movie is done.
They unexpectedly join forces with their old enemy Salacious Crumb and destroy the superweapon in a battle featuring a Sith educational display that uses Force Lightning to demostrate the dielectric breakdown of air.
P.S. Rey's parents are a random junk trader and BB-8.