With the new season coming soon, this is very helpful.

To begin with, spoiler alert because this entire article is summing up the events that happened over two seasons of TV. But you already knew that, right? Without going into too much detail, off the top of my head, here's what happened in the two seasons. A group of young boys have their lives flipped upside down when one of them, Will, gets abducted by an inter-dimensional demon/Demogorgon and taken into an alternate dimension. Will's mam gets obsessed with contacting him via Christmas lights. The gang meet an extremely powerful girl named Eleven that's telekinetic and can do all sorts of cool stuff. Mad shit ensues and it's all a loving homage to a whole load of '80s films that you loved. Elsewhere, a character named Steve Harrington is sort of a dick but he has outstanding hair, there's a sinister government organisation that are experimenting on kids, Dustin's smile is glorious. The season concludes with Will getting rescued, while the local policeman Hopper leaves some waffles for Eleven to find. Ignore all the #Justice4Barb stuff, she was annoying. Fast forward to Season 2. The big baddie from Season 1 - The Mind Flayer - is still about and he's messing with Will's mind again. We learn more about the weird government agency, Steve Harrington is actually the coolest man alive, Samwise Gamgee (Sean Astin) starts to date Will's mam. Elsewhere, Eleven goes off to make the most frustrating episode of TV ever, she returns to close the intergalactic portal, they all go to prom. Poor Bob. Oh yeah, Steve's hair is even better than before and he's now become a sort of father figure to Dustin...which is the greatest thing the show has ever done. To be honest, it's a far more complex plot than that and we do have plenty of questions about the Season 2 finale, but for the meantime, enjoy this brief recap of what unfolded in Hawkins, Indiana. With Season 3 of Stranger Things arriving on Netflix on 4 July, this seems like the perfect way to get reacquainted with the Upside Down. Take a look as Finn Wolfhard, Gaten Matarazzo, Noah Schnapp, Caleb McLaughlin and Sadie Sink tell you everything that happened on the show so far. Enjoy. https://www.youtube.com/watch?v=JpbWqiUy0YM Clip via Netflix