City of Ember is about a colony of people who live in the year 241. Their small city is on the verge of disaster: supplies are running out and they may be loding power. If the lights go out they will be plunged into absolute darkness and be unable to survive. Lina and Doon, two 12 year olds recently placed in jobs (Lina as a Messenger, Doon in the Pipeworks) set about rescuing the city of Ember.I got sucked into this book much quicker than I thought I was going to, and even though some things were predictable, and some of the "messages" were a bit too heavy-handed for me, all in all it was really entertaining and a great book for the age group. There are a few others in the series (The People of Sparks is #2), which City of Ember has me eager to read.