BTS are officially back, and making sure the whole world notices. On Feb. 3, RM posted a photo on his personal social media account with the caption, “BTS is back in business after four years.” The casual phrase instantly went viral among fans, signaling the group’s long-awaited return as a full lineup. In the relaxed selfie, RM wears a mask and brushes back his hair, but the understated image contrasted sharply with the massive scale of what followed. The post gained even more attention because it came just a day after all seven members departed together via Incheon International Airport for Dubai on Feb. 2 — their first full-group overseas schedule in nearly four years. The timing made RM’s message feel less like a joke and more like a declaration. The group is set to hold “BTS comeback live: Arirang” at 8 p.m. on March 21 at Gwanghwamun Square in central Seoul. The live event will celebrate the release of their new album “Arirang” and feature first-ever performances of new songs, including the title track, in one of Korea’s most symbolic public spaces. BigHit Music