Gain

Biography

Son Ga-in (손가인; born September 20, 1987), known mononymously as Gain, is a South Korean singer, actress and entertainer, best known as a member of the South Korean girl group Brown Eyed Girls. Having debuted with her home group earlier in 2006, Gain eventually made her solo debut in October 2010 with Step 2/4 to great commercial success, and has since released a total of six extended plays. In addition to her musical career, the singer also appeared in several native programs and series, most notably We Got Married and All My Love for You, where she co-starred alongside 2AM's Jo Kwon.

2005–2009: Brown Eyed Girls and solo projects

Son Ga-In was noticed by the existing members of Brown Eyed Girls after she was eliminated during auditions for the popular South Korean reality series, Let's Coke Play! Battle Shinhwa! She was approached by composer Ahn Jung-hoon and invited to audition at Brown Eyed Girls' company, Nega Network, eventually joining the group. The four members performed several small shows before officially debuting as Brown Eyed Girls in 2006. In the same year, she performed a duet "Must Have Love×Must Have LOVE6 November 2006 · SingleSpotify (search)YouTube Music (search)Tracklist · 9 tracks · 2 discsDisc 11Must Have LOVE (우리들의 겨울)4:172Must Have FRIENDS4:103Must Have LOVE (Melody version)4:174Must Have FRIENDS (Rhythm cut version)4:105Must Have LOVE (Instrument)4:176Must Have FRIENDS (Instrument)4:10Disc 21사랑을 만나다2Must Have LOVE (우리들의 겨울)3Must Have FRIENDS" with SG Wannabe's leader Kim Yong-jun, which became her first number one hit during the Christmas season.
Despite having initial successes, it was not until 2009 that her home group made a breakthrough into Korean mainstream with their hit song "Abracadabra", which was notable for the group's shift of their image and their new direction. After the unexpected success of the song, the group gained further recognition.
Beside her involvement with the group, she also appeared in 4Tomorrow, a collaboration project with 4Minute's Hyuna, After School's Uee and KARA's Han Seung-yeon. She also released a digital single, titled "I Happen to Love You" (우리 사랑하게 됐어요) with then We Got Married partner Jo Kwon of 2AM, composed by fellow member JeA, written by Kim Eana, and produced by Lee Min-soo. The duet became a successand spent three weeks at the top of the Gaon Digital Chart of 2010.

2010: Solo career debut and Step 2/4

In April 2010, it was announced that all the Brown Eyed Girls' members would pursue their own solo careers beside the group's activities. Gain became the second member to start her solo activities after Narsha by releasing her first mini-album, Step 2/4×Step 2/48 October 2010 · EPSpotify (search)YouTube Music (search)Tracklist · 6 tracks1Nitchell (Baby-G mix)2:102돌이킬 수 없는3:483Tango the Night3:554Esperando4:015가인 (歌人)3:136진실3:45, with "Irreversible" as the title track in October 2010, to critical acclaim from critics and public due to its strong influence of tango. The video for the track was then released on October 8, 2010, alongside the album's release. The mini-album also achieved modest success, peaking at number two on Gaon Weekly Albums Chart while the title track became her first solo number one hit. Gain worked with university professor Park Myung-soo (Seoul Arts University) on the tango-inspired choreography for "Irreversible". On December 21, 2010, "Bad Temper×Bad Temper21 December 2010 · SingleSpotifyYouTube Music (search)Tracklist · 1 track1Bad Temper3:27" was released as a digital download single. She then resumed her group activities after the end of the album's promotion.
After the promotions of Brown Eyed Girls' fourth album, it was revealed that Gain had signed a contract with LOEN Entertainment to manage her solo career.

2012–2013: Talk About S, Romantic Spring and "Gentleman"

Prior to the release of her second EP, Gain was featured on Yoon Il-sang's anniversary album Yoon Il-sang 21st Anniversary Album: I'm 21 with a cover of "For You Not To Know" (너만은 모르길). She also released a duet with JYP in April 2012, titled "Someone Else", to certain success, peaking at number two on Gaon Weekly Singles Chart.
However it was only after the release of Brown Eyed Girls' digital single "The Original" that her sophomore EP, Talk About S×Talk About S5 October 2012 · EPSpotifyYouTube Music (search)Tracklist · 5 tracks1팅커벨3:162그녀를만나3:343피어나3:504시선4:515Catch me if you can3:33, would be released on October 5, 2012, followed by teasers of the album's content. Reunited with long-time collaborators of both her home group and her previous debut album, such as lyricist Kim Eana, producer Lee Min-soo and Jo Yeong-cheol, the album was received with positive reacts from both critics and the public, while becoming her first release to take the top spot of Gaon Weekly Albums Chart, also her best selling release to date. Its title track, "Bloom", was also her best selling track and one of her signature hits. On November 30, 2012, "Nostalgia" was released digitally as a single, featuring rapper Eric Mun of boyband Shinhwa.
Later on April 8, 2013, Romantic Spring was released as a collaboration project between Gain and Korean singer Cho Hyung-woo, who later became her labelmate. The collaborative EP debuted at number three on Gaon Albums Chart. On April 13, 2013, she was featured in PSY's music video "Gentleman", along with the "arrogant" dance which was popularized in the Brown Eyed Girls song "Abracadabra". She then returned with Brown Eyed Girls' 5th studio album, Black Box, which was released on July 25, 2013, and later appeared as a guest performer for IU's "Everybody Has Secrets" (누구나 비밀은 있다) on her 2013 release. In the same year Gain parted with LOEN Entertainment and joined the APOP Entertainment roster, while making her first major appearance in film with The Huntresses.

2014: Truth or Dare

At the beginning of 2014, Gain released her third mini-album, titled Truth or Dare×Truth or Dare6 February 2014 · EPSpotifyYouTube Music (search)Tracklist · 6 tracks1진실 혹은 대담3:382Fxxk U3:393Q&A3:434Black & White3:235폭로3:476A Tempo (inst.)3:43, which featured lyrics from Kim Eana, Lee Hyo-ri and JYP, along with guest performers such as Bumkey and Jo Kwon, with the former being featured in the album's first single. Considered as a "bolder" move for herself, the album was preceded by "Fxxk U×Fxxk U27 January 2014 · SingleSpotify (search)YouTube Music (search)Tracklist · 1 track1Fxxk U3:37", which received mixed reactions from the public due to its theme dealing with domestic violence; however, it was praised by critics. The second single "Truth or Dare" (진실 혹은 대담) was released on February 6, 2014, to modest success, while the third single "A Tempo×A Tempo21 March 2014 · SingleSpotify (search)YouTube Music (search)Tracklist · 1 track1A Tempo3:43" was released digitally on March 21, 2014. Later that year, Gain was featured in Pitchfork's "20 Essential K-Pop Songs" list with "Fxxk U" and "Tinkerbell", the latter an opening track for her second mini-album. She also appeared as KARA's Goo Hara's friend in her own reality show Hara ON & OFF at the end of 2014.

2015–2019: Hawwah, Brown Eyed Girls' 10th anniversary and End Again

It was announced that Gain would go on to release her fourth solo mini-album (fifth overall), titled Hawwah×Hawwah12 March 2015 · EPSpotifyYouTube Music (search)Tracklist · 6 tracks1Apple3:032Free Will3:143Paradise Lost3:314The First Temptation3:375두 여자4:026Guilty3:07 in February 2015 as a follow-up to her previous Truth or Dare EP. The album marked the first time in her solo career to feature two title tracks, followed by a Bible-influenced concept. Released in March 2015, the EP eventually debuted and peaked at number five on Gaon Weekly Albums Chart while appearing at number nine on Billboard World Albums Chart, thus becoming her fourth top five entry and her first to chart in the US. Its singles, "Apple" and "Paradise Lost", peaked at number two and number six on Gaon Weekly Singles Chart respectively. As of April 2015, the album has sold 4,203 copies. She was later announced as one of the participants for JTBC's Going to School, a reality television show about idols going back to high school.
During an interview with Billboard, Gain announced that her home group would return with a new album to coincide with their tenth anniversary since debuting in 2006 and the possibilities of another solo release in 2015 also. Gain released the first part of her first full album, End Again×End Again9 September 2016 · EPSpotify (search)YouTube Music (search)Tracklist · 5 tracks1Carrie (The First Day)3:402Carnival (The Last Day)4:223반딧불이의 숲3:464비밀3:175Begin Again (inst.)0:56, on September 8, 2016. The title track was "Carnival (The Last Day)". As of 2024, the second part of her first full album, Begin Again, has not been released. In September 2019, she participated in Brown Eyed Girls' cover album, RE_vive.

2025-present: Return to industry

On December 17, 2025, Gain and 2AM's Jo Kwon released a remade version of their duet track "I Happen to Love You".

Filmography and television work

Gain appeared on We Got Married with 2AM's Jo Kwon starting from September 2009. Their virtual marriage came to an end after 15 months in January 2011. She made her acting debut in MBC daily sitcom All My Love for You. She was the female lead Hwang Geum-ji, alongside Jo Kwon, who played the role as her younger twin brother Hwang Ok-yeop. Her character was the love interest of Yoon Doo-joon (from BEAST) character also named "Yoon Doo-joon". However, owing to schedule conflicts, her participation in the sitcom ended in May 2011. In 2013, she became one of the three main female characters for The Huntresses, along with Ha Ji-won and Kang Ye-won. She also participated in JTBC's Going to School in 2015, along with other idols such as Taemin of Shinee and Seulgi of Red Velvet.

Legal issues

In July 2021, Gain apologized for illegally using propofol, an anesthetic drug prohibited from being used for purposes other than surgical treatments in South Korea. She was fined ₩1 million (US$883 in 2021) after being indicted for using propofol in an unspecified city in the Gyeonggi Province between July and August 2019. In an apology issued by Mystic Story, the parent company of Apop, it was stated that Gain "made a reckless choice due to severe depression and a sleep disorder." Following the incident, Gain was inactive in the entertainment industry from 2021 until making a return in 2025.