In Spider-Man: Far From Home, Peter Parker is recruited by Nick Fury to help stop the Elementals, only to discover that Quentin Beck is a fraud who faked them with holographic projections and drones. The recap below reveals the whole story, including the ending.
Peter's class tour of Europe is interrupted when Fury pulls him into the fight. Beck, nicknamed Mysterio, says he is from another dimension and has fought the monsters before. Peter bonds with him, and, feeling unready to be the next Tony Stark, he hands over a pair of glasses Stark left him that control a powerful defense AI.
That decision is the mistake the rest of the film pays for. Beck turns out to be a former Stark employee, and with the glasses in his hands he plans a bigger staged attack in London.
MJ works out that something is wrong, and Beck tricks Peter with illusions that leave him stranded and hurt. Peter recovers, builds a new suit and returns to London to fight the drones. He learns to rely on his spider-sense instead of his sight, and he wipes out the drones. Beck is killed when his own drones fire on him in the chaos.
Before he dies, Beck has recorded a video that edits the events to make Spider-Man look like the killer, and his team releases it after his death. Peter gets the glasses back, and he and MJ begin a relationship.