A young boy disappears while riding home at night, and his friends and the local police conduct a desperate search for him. Meanwhile, an unknown creature escapes from a nearby government energy lab, and the man in charge--Dr. Matthew Brenner--will do anything to get it back along with the girl who escaped from his custody.moreless
The boys take Jane back to Mike's house and try to find out what she knows about Will's disappearance. Meanwhile, Joyce tells Jim about the strange phone call that she received, and Jonathan confronts his father.moreless
Joyce manages to make contact with Will. Meanwhile, Nancy realizes that Barbara has disappeared, and the boys enlist Jane's help to find their missing friend.
Both Joyce and Mike believe that Will is still alive and try to contact him. Meanwhile, Jim continues his investigation into Hawkins Labs, and Nancy and Jonathan grow closer after Nancy realizes that Jonathan took a photo of the same monster that she saw.moreless
After he realizes that Joyce is right, Jim breaks into Hawkins Laboratory and finds the gate. Meanwhile, Jonathan and Nancy join forces to look for the monster, while Dustin gets an idea of how to find the gate and locate Will.moreless
Nancy narrowly survives an encounter with the monster, but gets into trouble with Steve. Meanwhile, Jim and Joyce investigate Terry's missing child, and Lucas strikes off on his own when Mike insists on searching for Jane.moreless
The government closes in on Jane and the boys, but Jim rescues them and everyone reunited to figure out a way to get Jane to the Upside Down and find Will.
While Jim and Joyce travel into the Upside Down to rescue Will, Jonathan and Nancy try to lure the monster to the Byers home. Meanwhile, the Army invades the middle school and tries to recapture Jane.moreless
The U.S. sends a fleet after the Colorado, while Marcus finds his judgment questioned by Prosser.
Betrayed, left with no other option but to run, the crew of the USS Colorado will have to fight for its survival.