[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 World Eater a space station capable of increasing the CO₂ levels in a planet's atmosphere, causing rapid heating.
They unexpectedly join forces with their old enemy The Space Slug and destroy the superweapon in a battle featuring Kylo Ren putting on another helmet over his smaller one.
P.S. Rey's parents are Obi-Wan and Amilyn Holdo.