[4] He played Oskar Schell in the 2011 feature film Extremely Loud & Incredibly Close.
[5][6][7][8] For his performance in that film, Horn won a Critics' Choice Award for Best Young Actor.
[9][10] He also played Jimmy Hawkins in the 2013 television film Space Warriors.
[11][12][13][14] Horn was cast in Extreme Loud & Incredibly Close after film producer Scott Rudin discovered him in Jeopardy!, where Horn was a contestant.
[15] He was to have appeared opposite Kris Kristofferson in a film titled Joe's Mountain.