[4] Nine days later, it was reported that the group finished filming the music video for the title track, which was produced by JYPE founder Park Jin-young.

[5] On May 1, Twice shared an image teaser through their official SNS channels featuring the nine members wearing school uniform-styled outfits and confirmed the release of their fourth extended play titled Signal on May 15.

They also released the schedule of promotion for the album, including the two-day encore concert of Twice 1st Tour: Twiceland – The Opening on June 17–18, which was to be held at the Jamsil Indoor Stadium in Seoul.

[9] Individual image teasers of the members, posed with both hands on their heads using letter Y of the American manual alphabet that look like two antennas, were released over the next few days.

On May 3, individual teaser photos of Nayeon, Sana, and Dahyun were uploaded, alongside the full track list for the album revealing six songs in total.

Later that day, a new set of individual image teasers were released depicting Nayeon, Sana, and Dahyun to have their respective powers of time manipulation, invisibility, and self-duplication.

A second batch of photos was released later in the day depicting the three members to have the powers of time stopping, enhanced vision, and telekinesis, respectively.

[23][24] On May 10, a third teaser clip featuring Jeongyeon, Sana, and Chaeyoung, alongside a short group shot of Twice by the end, was released.

[25][26] On May 11, an intro clip for the group's "Signal" music video was uploaded, featuring an alien character roaming around a forest.

The eponymous title track, written and produced by Park Jin-young, alternates between a hip-hop rhythm with a Roland TR-808-style kick and dance-pop mixed with electronic music.

The song "Hold Me Tight" features the usage of synth music and lyrically talks about a girl's sorrow of hoping for a quick confession from her romantic interest who is oblivious to her feelings.

[34] JYP Entertainment denied the report about the group's plan to promote the EP for only two weeks due to their Japanese debut in June.

[39][40][41] Twice held a media event at Blue Square Samsung Card Hall in Hannam-dong, Seoul, before the release of the EP.