We start with a devastating earthquake that leads to the trapping of our characters. While trying to survive inside of a cavern created by a collapsed freeway there are so many ups and downs. Dangerous convicts, a pregnant woman, trying to escape, falling in love and more. No only do the characters go for a ride but I did also as a reader. It was easy to become emotionally invested in the wonderful characters that Ms Sorenson gives us. I don't want to say any more because I might give it all away. But seriously, read it now, this is an adventure you don't want to miss.