In this work performed in 1976 (edited to a video work in 1981), Imai flashes a strobe light directly at the audience seated inside the auditorium in the KBS Laseirum Center in Kyoto and photographs their reaction with his camera. The audience who had expected to see a moving image projected on the surface of a dome-shaped screen on the ceiling is submerged in the dark for the first few minutes. They are left to listen to the recorded sound of a heartbeat and the metronome set to the rhythm of 6/8 time. The sudden eruption of the strobe light as Imai presses the shutter of his camera synchronized to the ringing sound of the metronome brings out diverse reaction from the audience: some cover their eyes with their hands or the pamphlet, while others directly look at the camera and strike some funny poses.