What happens in the city of ember, book 1?

City Of Ember Book 1: SummaryAfter the Earth's destruction. Lina Mayfleet, and Doon Harrow are two children in Ember who find themselves on a mission to save their dying city. The city's lights are beginning to flicker and food supplies are running out. Doon lands a job at the Pipeworks where he wants to try to repair the failing generator. The find the builders instructions to leave the city, and they go to a new place, with a sky of blue, and grass, the color of green. They have just discovered that they were living underground.