Iron Man 3
One night, Harley Keener felt the presence of someone in his garage, the intruder turned out to be Tony Stark. The boy and Stark were the site of a thermal explosion and then went to visit a woman, whose son was causing the explosion. At that meeting does not end because Stark meets Ellen Brandt and Eric Savin, with whom they fight to stay alive.
Afer the Brandt's death, Savin taking hostage to Harley but the child escapes through a flash grenade given to him by Tony. One day coming from school, Harley finds his garage was full of electronic equipment which with filled him joy. On a table was a personal gift with a sign that read: "Potato Gun Mark II" and regards from "The Mechanic".