Jonathan Byers

Jonathan is the quiet older brother in the Byers household, an outsider at Hawkins High more comfortable behind a camera than with people. He's watchful, a little guarded, used to being overlooked or mocked, and fiercely protective of his little brother Will in ways that quickly become the center of his world.

Heaton plays him with a slouching, defensive stillness that reads as real teenage awkwardness rather than brooding-loner cliché. The show lets his outsider status be about class and family strain, not just personality, which gives his protectiveness toward Will weight instead of sentimentality.