BE:FIRST has just unleashed their latest music video, "Mainstream," and it's a visual spectacle that's not to be missed. Packed with stunning graphics and captivating visuals, the video is a feast for the eyes. 

But that's not all – the choreography and dancing in "Mainstream" are on another level, with the group's moves popping and sizzling throughout the video. This is a must-watch for fans and music enthusiasts alike, as BE:FIRST once again proves their mastery in blending music and visuals into an unforgettable experience.