When Eli's family gets word that a nuclear bomb has been launched, they have, at most, about 40 minutes to find shelter. Fortunately, Eli's billionaire father saw this coming: he's constructed, and stocked, an underground compound that can support them for the next fifteen years while they wait for the radiation to clear. Eli is pushed into the shelter with his mom and sisters, but as Dad seals the hatch, he notices two people still missing: his grandmother and his twin brother, Eddy. It's too dangerous to go back out for them. And Eli knows it was his fault that they got left behind. 
 Now six years have passed. The food stores have been contaminated--or sabotaged. Dad's acting a little weird, and his smooth answers about the sporadic internet access seem too rehearsed to be the truth. There's only one way out--and the person who knows it is the one who won't let them leave. 
 It's an engrossing, page-turning story, moving quickly through a number of betrayals and deceits. At times it moves too quickly: the shift from "we have nothing but time" to utter urgency is jarring; Eli is not by nature a suspicious teen and his embrace of doubt is very sudden. The writing varies in quality from mediocre to painful, but the plot is compelling enough to carry the reader through regardless. I'd pass this along to teens interested in post-apocalyptic survival, but not without also recommending Z For Zachariah or other titles.