The group's label YG Entertainment released posters with each member of Big Bang on different dates to promote the songs of the EP Alive, before its release. On February 17, 2012, the last poster was released containing G-Dragon introducing "Blue", which would be released as the first single from Alive. The song was released one week before the EP on February 22, 2012. The song's music video was filmed in New York City and directed by Han Sa Min. American producer Justin Noto, that selected the places for the filming along with Jesse Roberts, commented that the group was "interested in a look that seemed like the drudges of New York, the old 1970s feel." A Japanese version of the song was included at the Japanese studio albumsAlive and the greatest hits albumThe Best of Big Bang 2006-2014.
Composition and reception
"Blue" is a mellow mid-tempo track, guitar heavy and melodic. The title "Blue" represents the lyrical-content of the song, that talks about the sadness one feels when they lose a love. The message of the track is how to find rejuvenation in the face of accepting sorrow and loss. "Blue" expresses a more emotional side of Big Bang that has been hidden before. The members explained that the track is "about being lonely, or feeling empty. Sorrow? All the pain turning blue. Sort of being comforted, it’s that kind of warmness." The Borneo Post described the song as an throwback recipe "with hints of modernism," calling it a "therapeutic confession." Kaitlin Miller of Sun-Times included the song in their list of best Big Bang songs, calling "Blue" a "smooth, emotional track". Miller also felt that the single highlighted "a more mature sound" from the group, and that it contained more "interesting electronic samples and production techniques" compared to their previous work.
Commercial performance
As soon as it was released, the song charted at number one in all of Korean online music charts, including Melon, M.net and Soribada. "Blue" debuted at number one on the Gaon Digital Chart and on the K-pop Hot 100, and remained at the first spot for three weeks in both charts. The single had the highest first week sales of 2012 and the biggest debut sales of a boy band song of all time in the Gaon Chart, gathering 833,233 downloads. On its second and third weeks, additional 537,161 and 348,535 digital units, respectively, were sold. "Blue" also debuted at number one on the Gaon Streaming Chart, recording over 2.1 million audio streams. It remained atop of this chart for another three weeks, totalling four weeks being the most streamed song. Even though it was released in the last week of the month, "Blue" was the best-selling song of February, and the most streamed song of March. The single finished 2012 as the fourth best-selling song of the year. With over 3,5 million digital downloads in South Korea, "Blue" is one of the best-selling singles in the country.
