"Mr. Brightside" is the first single released by American rock band The Killers. It was released as the band's debut single and is featured on their debut studio album Hot Fuss (2004). Written by band members Brandon Flowers and Dave Keuning, this was one of the first songs the Killers ever wrote. It is written in the key of D-flat major. Two music videos were made for the song: the first, which is in black-and-white, features the band performing in an empty room. The second, filmed for the re-release, is based on the 2001 film Moulin Rouge!.