A party of New Zealand scientists visit White Island off the coast of the North Island to study its thermal activity, structure and mineral deposits. This film illustrates their work and environment: the disused sulphur mill which was the site of their base camp; measurement of temperature in boiling pools to record shifting thermal activity; determination of the acidity of liquid in these pools; examination of the volcanic crust including the mosaics of caked mud and ash; study of the island’s birdlife.