Introduction -- Part one: The rocks of volcanoland and how they erupt. The molten Earth : what causes Earth's volcanoes? -- Journey to the surface of the Earth : who do volcanoes erupt in difference ways? -- Reading the rocks : how do we understand past eruptions and predict future volcanic hazards? -- Part two: The gases of volcanoland and their global effects. Breath of the Earth : what messages do volcanic gases carry from the deep? -- Volcanic winter : how can big volcanic eruptions briefly chill the planet? -- All in the balance : how do volcanoes help keep Earth's long-term climate stable? -- Part three: The reach of volcanoland through outer space and deep time. Home truths from the heavens : what is the nature of volcanism on other worlds? -- Mass extinction : did large-scale volcanism trigger past extreme environmental change? -- Epilogue.