On 17 Oct, explosions were particularly violent at Anak Krakatau. We show a series of images of a spectacular explosion captured from close range by boat. 2 months later, the cone of Anak Krakatau collapsed into the sea on the evening of 22 Dec 2018, triggering a catastrophic tsunami. The following sequence of pictures was taken within few seconds from each other each. (Photo: Tom Pfeiffer)