Cloak Dagger (1984)

4K UHD - 
With his mother dead and his father, Hal Osborne (Dabney Coleman), busy working, 11-year-old Davey (Henry Thomas) spends his time immersed in video games, often dreaming up espionage stories featuring imaginary spy Jack Flack (also Coleman). When Davey sees the murder of an FBI agent, the dying man hands him an Atari video game cartridge with military secrets. No one believes his story, and Davey is forced to go on the run, escaping from attempts on his life with Flack's guidance.