The band was revving up the crowd at the private, beachside concert, the lead singer punctuating musical notes with pumping fists - "We. Are. Seventeen!" - unaware of the approaching danger.
As he walked across the stage Saturday night, a tsunami wave hit the shore of Tanjung Lesung beach on the western tip of Java, knocking the stage out from under the band and bringing the concert to a sudden and tragic end.
In a video recorded by someone standing several yards away, the stage - with the band members on it - briefly floats as the water hits and then is washed away. Band members disappear underwater. People in the audience scream as they try to flee the approaching seawater and music equipment. Then the video abruptly ends.
According to Reuters, four people connected to the band were killed: bassist M. Awal "Bani" Purbani, road manager Oki Wijaya, guitarist Herman Sikumbang and crew member Ujang.