Once, TWICE — too much is never enough when it comes to one of South Korea's hottest exports at the moment.

The unstoppable "TT" girl group is back for their latest comeback in May, just three months after their album repackage Twicecoaster: Lane 2 featuring their latest smash hit "Knock Knock" — and one month before making their Japanese debut with #Twice.

Signal will be the group's fourth mini-album thus far, and will be released on May 15.

On May 1, Twice unveiled their promotional schedule for Signal, which includes daily teasers leading up to the album's release on May 15. They've also revealed some of the packaging for the new album with today's pre-order, which includes photo cards and posters, as well as random CD-R designs and different covers. (There's an endless array of combinations, basically.)

Along with the new mini-album, Twice will release a music video on May 15, along with a showcase with V Live later that evening. They'll also be performing an encore of their first solo tour, the Twiceland concert, at Jansil Indoor Stadium in Seoul on June 17-18.

While the first promotional photos imply that the girls will be serving up a school girl concept this era, the album's galactic packaging suggests something more space-age is afoot.

The album's title track is reportedly produced by JYP Entertainment founder J.Y. Park himself, as teased on Instagram.

UPDATE (May 3): The group's teased individual promo photos, plus the track list for Signal! The 6-track mini-album includes the J.Y. Park-composed title track "Signal." as well as "Three Times a Day" (하루에 세번)," "Only You (Only 너)" (featuring lyrics by Wonder Girls Park Ye-eun!), "Hold Me Tight," "Eye Eye Eyes" and "Someone Like Me."

UPDATE (May 8): The first teaser trailers for "Signal" just beamed in. Watch!

UPDATE (May 9): A third extended "Signal" teaser trailer has arrived. What's that in the sky?

UPDATE (May 10): Gulp. We have contact. Watch the opening of TWICE's new music video, which features a very special, out-of-this-world guest.

UPDATE (May 11): A "Signal" spoiler featuring all of the promo photos released thus far has just arrived — but that beat, tho. Just a few more days!

Stay tuned. There's more to come...

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