It doesn't really matter though, because I thought Pan was just as awesome as Del.
The book is set up as a back and forth "then" and "now." "Then" was back right after Alex and Lena crossed into the Wilds and how Lena was found by a group of Invalids and nursed back to health and then brought into their community. "Now" is set in NYC where a powerful political group is pushing vaccination for the love disease at a younger age. There's a lot of unrest, as many disagree with the idea of curing folks at a younger age, as it can result in death and things worse than death. Lena and her gang are part of the Resistance and trying to do what they can to fight for freedom for all.
Again, this is definitely an action-driven book. If you like action novels, you will love this. If you don't, but you loved Del, you will still love it because you already care about the characters.
This book left me counting the days until the conclusion of the trilogy.