The Opening: Rosewater's annual healing
In 2066 Nigeria, an alien biodome called Utopia City (the alien entity is known as Wormwood) opens once a year. Thousands of pilgrims camped around it are cured of cancer, blindness and other conditions, and the dead nearby rise as mindless 'reanimates.' The town of Rosewater grew up around the dome to serve and exploit these pilgrims, and it becomes the test case for what happens when a community's economy and hope are built around an alien benefit nobody understands.
