In lucid and energised prose, Emily Mayhew summons the four horsemen of the apocalypse; the collective threat to humanity bearing the names of war, pestilence, famine and death. From their first appearance in Revelations they have remained in human consciousness ever since, spanning time and space and evolving as new scientific discoveries and advancements in technology alter the world. Mayhew examines in detail the four afflictions faced by humanity throughout history and shows, that despite our pessimistic view of the future there are people from all walks of life – scientists, doctors, engineers, biologists, statisticians, app developers, historians, NGOs and volunteers – who are making the world a safer place. The line stretches all the way round the world and its strength comes from common purpose.