Helena (song)

"Helena" (alternatively titled "Helena (So Long & Goodnight)") is a song by the American rock band My Chemical Romance from their second studio album, Three Cheers for Sweet Revenge (2004). It was released as the album's second single on March 8, 2005. An emo song, it was created in memory of band members Gerard Way and Mikey Way's late grandmother, who died while the band was touring and unable to visit her during the last year of her life. Although it was one of the last tracks on the album to be written, the direction that Gerard Way took it in influenced the rest of Three Cheers for Sweet Revenge's tracks. A music video, directed by Marc Webb and filmed at a church in Los Angeles, was also released.

The song and its music video were well received by critics. It was a commercial success, charting in several countries and becoming the band's first major hit on the Billboard Hot 100, as well as reaching number one on the UK Rock & Metal chart. It has been certified gold by the Recording Industry Association of America, British Phonographic Industry, and Recorded Music NZ. The song was nominated for five awards at the 2005 MTV Video Music Awards, although it did not win in any of the categories.

"Helena" is often considered by journalists to be the band's breakout hit, a contributor to the commercial success of Three Cheers for Sweet Revenge, and an influential track on the emo music genre. Some have considered it as one of My Chemical Romance's best songs, as well as one of the best emo and goth songs in history. It is among the band's most played songs at live concerts, typically being used as a closing track.