 Previously, on Stranger Things. The season opens with Mike, Dustin, Lucas and Will playing a game of Dungeons and Dragons and offending off a monster they called the Demogorgon. However, on his way home, Will faces a monster of his own and is abducted. The next morning, Will's mum Joyce and his brother Jonathan realise he's not there and start to panic. At school, the boys also realise Will is missing while being bullied by a couple of mouth breathers. We then meet Mike's sister Nancy and her best friend Barb, who's concerned about Nancy's new relationship with the school heartthrob Steve. We're introduced to the local sheriff Jim Hopper, who Joyce talks to about Will's disappearance. Meanwhile, a local government facility is suiting up and venturing into an alien looking gateway and we learn that a young girl recently escaped the facility. Her name is Eleven. Eleven sneaks into a nearby diner for something to eat and makes friends with the owner of the establishment. We learn that Eleven has special abilities before the owner is murdered and Eleven escapes once again. The boys are told not to go looking for their friend as the search escalates. Joyce receives a shocking phone call from Will and the boys go looking for Will despite their warning but come across Eleven instead. They take Eleven home to Mike's house where she sleeps the night in the basement. Mike learns of the bad men coming after Eleven and Eleven learns the basics of modern life before recognising Will in one of Mike's pictures. In a flashback, we're showing the awful test that Eleven has been put through because of her powers and the leader of the operation, Dr Brenner, is seen as her fatherly figure who she calls Papa. The boys then learn of Eleven's powers as Hopper continues searching for Will, who Eleven explains is in a place known as the Upside Down, being held prisoner by the Demogorgon. Elsewhere, Nancy and Barb attend a party at Steve's parents' house which Barb does not approve of. Nancy then ditches Barb before she is photographed by Jonathan and disappears into the night. Joyce receives shocking phone call number two and discovers that Will is talking to her through the electricity and let's just say her household gets pretty lit. Hopper starts investigating the government facility and Nancy realises that Barb is missing. Joyce meanwhile makes progress contacting Will before the Demogorgon reveals itself to her. Hopper discovers the facility is caught up in multiple lawsuits but all hope is soon lost when Will's dead body is recovered from a river. However, Eleven manages to tune into Will's singing on Mike's walkie-talkie. Joyce and Jonathan identify Will's body but Joyce refuses to believe the corpse is her son. The police start looking into Barb's disappearance and Nancy and Jonathan admit to each other that they saw a faceless creature the night Barb vanished. The boys prepare Eleven to be taken out in public and they all attend a school assembly for Will, where Eleven teaches the mouth breathers a lesson. Hopper starts to connect the dots and discovers Will's body is a fake. He breaks into the facility and discovers what is really going down there, then suddenly wakes up in his house where he finds a bug in his light fixture. Nancy and Jonathan go looking for the faceless creature and the kids go looking for the entrance to the upside down which Eleven stops them from finding for their own safety. Nancy finds the entrance before confronting the Demogorgon then is saved by Jonathan who Stephen is getting jealous of. After sabotaging the boys' plan Eleven runs away and steals some egos which is her favourite food from a local grocery store. Hopper confirms Joyce's suspicions and they talk to a severely disabled woman who lost her daughter to the government facility. Nancy and Jonathan equip themselves to fight the Demogorgon before Jonathan is arrested for fighting Steve. Hopper and Joyce then team up with Nancy and Jonathan as they are looking for the same enemy. The boys have an encounter with their bullies which causes Mike to jump off a cliff however he is saved by Eleven who returns and breaks the bullies arm. However the bad men track down the children who are now on the run and Eleven saves the day again by flipping one of their vans. Steve ends up being one of the good guys and Hopper finds the kids. Eleven tries to communicate with Will to no avail however she thinks she could do it if her senses were blocked out and she was submerged in water. She then finds Barb's dead body and encourages Will to hold on a little longer. Meanwhile Hopper and Joyce break into the facility to find Will before they are captured by security. Hopper then makes a deal with them to allow Joyce and him into the upside down. While in there we see flashbacks of Hopper's daughter who died of cancer at a young age. Nancy, Jonathan and Steve lure the Demogorgon to the house and try to trap it but fail. Mike confesses his true feelings for Eleven before the bad men arrive to take her away but are interrupted by the Demogorgon who kills them all. Joyce finds Will on the brink of death but Hopper resuscitates him. Eleven grows weak but uses her last ounce of strength to disintegrate the Demogorgon taking her with it. Will recovers in hospital when Hopper is seen getting into a government vehicle. One month later and we again see the boys playing but Mike still misses Eleven. Nancy ends up back with Steve and Will is still suffering from his experience in the upside down. Hopper is then seen leaving Ego's in the woods.