I really enjoyed Delirium. The plot was nice and interesting for a first book but I kind of didn't like Alex and Lenas relationship that much. But then 
 Pandemonium happend! And I loved it! 
 It is seriously a great book and I enjoyed it so much more than the first one! 
 Julian is a great character and the chemistry between Lena and him is lovely! 
 This one is the best out of the series. Sadly the last one destroyed the whole premise of the first two books.