Boy group A.C.E. has redesigned the stage for the hidden Golden Track "Callin" selected by fans.

A.C.E. appeared on "Hidden Track 2," which aired live on April 22 in the season, and had time to find "hidden masterpieces that would be better known." On the opening stage, A.C.E. performed the first full-length stage of the Hong Chang-woo project's first song "First Love," which involved Jun, Dong-hoon and Chan. A.C.E. earlier called for explosive reactions from fans with a full-fledged stage that is more upgraded than the vocal line's sensibility shown on music shows.

When MC Lee Teuk asked about the recently released song "First Love" by vocal line Jun, Donghun and Chan, "As a matter of words, first love remains in the corner of my heart whether it's good or bad. It is a song about a heartbreaking and sad feeling that one cannot erase one's first love. It was the first full-fledged stage for "Hidden Track," he said, touching the production team.

Before the recording began, A.C.E. personally selected the candidate songs through a pre-meeting with the production team. Jun recommended "I Feel So Lucky" and Chan recommended "Take Me Higher." Kim Byung-kwan mentioned "Callin" at the time, saying, "It was a pity that the activities were so short at the time."  When Dong-hoon recommended "5tar," Chan said, "It's my favorite song among our songs. I cried every time the fans gave me an event and I cried every time I sang it," he said, selecting a total of seven candidate songs himself.

Chan predicted "5TAR" as a golden track chosen by fans expected by A.C.E., while all other members expected "Callin" as the No. 1 song.

The seventh-ranked song was "Maybe," the OST of the drama "My Love Healing." Chan said, "This is the first OST song that I and Byeong Kwan participated in. It's a very sweet and exciting song, so they asked me to sing it with a lovely feeling when I sang it, but it was really hard," he said. Kim Byung-kwan also said, "I used to like singing pop songs from a long time ago, but I usually listen to Usher or Chris Brown's songs. As a result, I sang it groovyly when I first recorded it, but I recorded it more than 20 times while re-recording it again,"

The sixth-ranked song was "Love is Beautiful Life is Wonderful" OST "Start" by Kim Byung-kwan. Kim Byung-kwan said, "I also agonized between 'Maybe' and 'Start.' I didn't think that the fans would give me a high ranking because the OST was not sung by all the members, but because I sang it separately," he said. At Leeteuk's request, Jun and Wow showed a sweet couple's performance as male and female protagonists in "Sapul Inn Pool," while Dong-hoon, Byeong-kwan and Chan instantly sang the OST sweetly, drawing attention.

Coming in fifth was "Where You Are," the OST for the drama "The Game" sung by Jun and Chan, while the fourth-place song was "CD Only Ver.," beating A.C.E.'s expectations. Ace said, "It's our first fan song and we delivered the message we wanted to give our fans as we wrote the lyrics. At first, Chan released the song with four members due to his other activities, but when he rejoined the group, he re-released the full version. Chan sang all the ending parts," he hinted.

The third-place song was "Take Me Higher," which was followed by a big twist. A.C.E. said, "It's the title track of our mini-album 'A.C.E Adventures in Wonderland' released in 18 and it's re-released as a full-length version after Chan joined," and Wow, who made headlines for his unique rap-making, wrote an acrostic poem with 'A.C.E.'E. As a result, it was a pleasant experience to be on stage where I could shout with my fans," he said.

"I Feel So Lucky" and "Callin" were selected as finalists for the Golden Track, and they shared episodes about each song. The first candidate song, "I Feel So Lucky," said an artist named DJ HCUE, who is working in France, who made a proposal for featuring, and for the first time, I'm going to sing a song that's all in English. With this song, I'm going to visit Paris during my European tour and appear on a famous TV show with a ratings of around 50 percent," he said.

As for "Callin," Dong-hoon said, "It was the title song of our second album, but it was a song like a sick finger because we only performed for about two weeks in line with the time we appeared on the audition program," and Jun also said, "I think the fans would want to see it properly because we didn't do well after the presentation." The final Golden Track song selected by fans was "Callin," which received a total of 22.1 percent of support.