“Lonely Day” is a song by System of a Down, from Hypnotize. Contrary to popular belief, this song is not about Daron Malakian’s brother, because he is an only child. He wrote this song and provides lead vocals on it. This song has a heavy guitar solo at the end, with a dreary theme throughout.

The song appeared in Disturbia, a 2007 movie starring Shia LeBeouf which was about a kid who stays on house arrest and watches his neighbors to pass the time. The song appeared in a sequence in the movie where Shia’s character tries to find ways of keeping himself from dying of boredom.