Dustin found a creature in the trash can and took it inside. He called it Dart. 

Will pulled Mike aside to let him know that the creature was making the same noises as the one from inside the alternate reality. 

Mike sided with Will and they tried to destroy it, but it grew legs and ran away. Eleven then returned and knocked Max off of her skateboard because she was close to Mike. 

Nancy decided it was time to tell Barb's parents the truth, but she did not know she was being listened to by the villains. 

Joyce looked up the camcorder footage and found the bullies, but she also found a trace of the monster Will drew and she realized her son was not better.