ASTRO has shared a new look into what fans can expect from their long-awaited comeback!

The K-pop boy band revealed the title track "Knock" of their seventh mini-album "GATEWAY" in their official SNS on April 21.

Fantagio, ASTRO's agency, released the teaser poster of their upcoming comeback, which shows multiple doors leading into another world, adorned with a dazzling galaxy and sparkly starbursts.

Arohas are highly-anticipating "Knock," the song participated by Jin (BTS), as well as lyrics penned by famous artist Lee Seu Ran, who has worked with BTS, SHINee, Red Velvet, GOT7, and more. Also, members Jin Jin and Rocky themselves wrote the rap verses for the track.

ASTRO's seventh mini-album "Gateway" is set for release on May 4.