3.5 stars for an engaging and enjoyable read. It's unavoidable to compare the second book in the series with the first, which had the advantage of introducing us to new characters and a new world. The continuation cleverly allowed readers to play with characters and settings from both time periods explored in the first novel. Time spent in the first time period moved forward with a great sense of urgency reminiscent of, though not as highly charged as in The Passage. Time spent in the second time period during The Twelve lost that sense of urgency. I felt it became more a meeting of friends, and I always had the sense that no one in the group of friends was in real danger, they'd always be pulled to safety by the author.