Panic! at the Disco (stylized for a time as Panic at the Disco) is an American band from Las Vegas, Nevada, formed in 2004 and features the current lineup of vocalist and guitarist Brendon Urie and bassist Dallon Weekes, who are supported by touring members Kenneth Harris on lead guitar and Dan Pawlovich on drums. Founded by childhood friends, Ryan Ross, Spencer Smith, Brent Wilson and Brendon Urie, Panic! at the Disco recorded its first demos while its members were in high school. Shortly after, the band recorded and released its debut studio album, A Fever You Can't Sweat Out (2005). Made known by the top ten lead single, "I Write Sins Not Tragedies", the album eventually was certifieddouble platinum in the US. In 2006, founding bassist Brent Wilson was fired from the band during an extensive world tour, and subsequently replaced by Jon Walker. Influenced by 1960s rock bands, the Beatles, the Zombies and the Beach Boys, and preceded by the hit single, "Nine in the Afternoon", the band's second studio album, Pretty. Odd. (2008), marked a significant departure from the sound of the band's debut, and ultimately led to the departure of guitarist and principal songwriter Ryan Ross and bassist Jon Walker, who favored the band's new direction. The duo subsequently formed a new band, the Young Veins, leaving Brendon Urie and Spencer Smith as the sole remaining members of Panic! at the Disco. Continuing as a duo, the band released a new single, "New Perspective", and recruited Dallon Weekes (bass) and Ian Crawford (guitar) to accompany the band during live performances. The band's third studio album, Vices & Virtues(2011), marked a return to the band's initial Vaudevillian pop-punk sound and was recorded solely by Urie and Spencer with producers John Feldmann andButch Walker. In 2012, the band added touring bassist Weekes to its core lineup, rendering the band a three-piece,and released its fourth studio album, Too Weird to Live, Too Rare to Die!, in 2013. On April 28, 2014, the band announced a Nicotine EP, which was released on May 6, 2014. The EP includes two songs previously released as bonus tracks on the Japanese edition of Too Weird To Live: "Can't Fight Against the Youth" and "All the Boys", along with an instrumental of "Nicotine".

Music critics named a number of different genres to describe Panic! at the Disco's music, including emo, pop punk, electro, vaudeville, and b aroque pop. Panic! at the Disco went on record many times saying that their second album would be completely different from A Fever You Can't Sweat Out, as Rolling Stone wrote in an article: "The group cemented its next direction with their first single, called "Nine in the Afternoon". "It's influenced by the music our parents listened to: the Beach Boys, the Kinks, the Beatles", says Ross. "Our new songs are more like classic rock than modern rock. We got older and started listening to different music – and this seems like the natural thing to do right now." Pretty. Odd. has been described as being like "[Panic] dropping the entire Beatles catalog into a blender, adding some modern alternative ice and the horn section from Sonia Dada, then churning out a new-millennium Liverpool smoothie." In his review of their live album, Stephen Thomas Erlewine noted, "...Pretty. Odd. suggests that they're becoming that rare thing in 2008: a pop-oriented rock band. They might not be doing this knowingly, but the results are entertaining all the same." Since the release of Vices & Virtues, the band's musical sensibilities have returned to the theatrical pop rock of their debut, albeit more mature and restrained in the style of Pretty. Odd. Urie has gone on record several times claiming that this was not the band's intention, stating that Virtues is a rebirth for the band and indicative of a new identity following the departures of Ross and Walker. Their fourth album Too Weird To Live, Too Rare To Die made way for the band to experiment with electronic music and synthpop.