They returned to Korea in late 2011, to garner further success and critical acclaim with their fourth album and its lead single "Sixth Sense".

Narsha was chosen when Jea remembered her as a "talented singer" from her school days, and Ga-in was selected by the three members after she was eliminated from the reality competition series Let's Coke Play!

[6] On March 2, 2006, after three years of formal training, Brown Eyed Girls released their debut album Your Story, simultaneously with its lead single "Come Closer".

[citation needed] After a short break, the group went back into the studio to work on their second album Leave Ms. Kim (떠나라 미스김), which included their R&B single "You Got Me Fooled" (너에게 속았다).

Subsequent singles were "Oasis" (오아시스) featuring Lee Jae Hoon and "It's Mine" (내꺼야), a collaboration with fellow group SeeYa.

During the break between their debut and second albums, Brown Eyed Girls released their first digital single entitled "I Am a Summer" (내가 여름이다), which was later included in their second LP.

As the group sported a substantially more provocative style, criticism arose over the suggestive and erotic themes that the video presented.

[11] The group next released the repackaged edition album entitled Sign that included the lead single of the same name, with "Drunk On Sleep," and a remix of "Abracadabra."

In July, Narsha released her first solo album 'NARSHA' to certain success,[13] In August, JeA collaborated with Rattpoom, a Thai singer, on his song 'Face to Face'.

Due to Brown Eyed Girls' overseas promotions Narsha decided to leave the show, with her last broadcast on December 28, 2010.

[16] The group ended the year with a concert entitled "Hot Winter Party" held in the Ax-Korea Hall in Seoul.

[citation needed] Representatives of their agency, NegaNetwork, stated that the concept for this album was to be “freedom of expression through music experienced via the sixth sense".

[20]They kicked off their promotional cycle officially with a double stage performance of "Hot Shot" and "Sixth Sense" on September 24 on Music Core.

[22] They also broke the jinx of going into a slump after a big hit, as the release was even more popular and received higher digital sales than their famed song Abracadabra.

[23] The band concluded their "Sixth Sense" promotions after a month but immediately followed it with the release of a repackage of their fourth studio album.

Gain became a CEO of a public relations company called ‘Mental Breakdown' particularly for the show, "OnStyle's Launch My Life – Ga In's Fashion King."

While Miryo was included in Mnet's hiphop program Show me the Money, collaborating with a rookie rapper to compete against other contestants for the top spot.

[32] Before the year ended, fans of Brown Eyed Girls were finally able to see all four members up on stage together once again for their 19+ Rated ‘Tonight 37.2 °C‘ concert.

[34] Gain also surprised everyone by releasing a duet album on April 7 with label-mate Cho Hyung Woo, titled "Romantic Spring."

[36] In October 2013, Ga-In also broke onto the CPOP scene, featuring in Show Lo's music video for "愛投羅網 (Cast The Net Of Love).

"[37] On November 4, multiple sources in the entertainment field revealed that Miryo and Narsha will be forming a sub-unit and plan on releasing music for the unit in mid-November.

[39] At the end of January 2014, Gain was revealed to be making a comeback with her 3rd mini album Truth or Dare on February 6,[40] releasing a teaser picture along with the news.

The song was created by lyricist Kim Eana and composer Lee Minsoo (who also worked with Gain on her previous solo single "Bloom").

On September 4, 2015, members JeA, Narsha, and Miryo became free agents after deciding not to renew their contracts with Nega Network.

[45] On October 26, Mystic released the first batch of teaser pictures through Brown Eyed Girls's official Twitter account.

"Brave New World" was written by Kim Eana and composed by Lee Minsoo, who had also worked together on previous Brown Eyed Girls songs.

The group appeared on the smartphone broadcast V App on the 29th where they stated that "Brave New World" had a choreography-heavy video but that they could not actually reveal any more info about the album.

The girls held their first showcase of their careers called 'Comeback to the Basic' on November 4 where they also performed the track "Time of Ice Cream".

Youngest member Gain revealed during the showcase that she took part in choreographing "Warm Hole" and "Brave New World", as well as forming the concept for their sixth album.

[58] For their 10th anniversary, the group held a concert with Kero One and KRNFX on March 18 at the Feria (now known as Club Bound LA) in Koreatown, Los Angeles, CA.