Unfortunately, Alex tells Lena he is not cured, but is an Invalid who grew up in the Wilds outside of the cities. They talk and agree to meet each other at the beach the next day. Because of this, the two girls begin to drift apart, but not before Alex appears before Lena again, at one of the illegal parties. She also starts going to illegal parties, and Lena is frightened for what will happen to Hana if someone discovers she is breaking the rules. Hana begins to listen to underground music. She believes he is a security guard who has already been cured. Later, she sees him again and finds out his name is Alex. The Invalids loose cows into the labs, and Lena sees a boy laughing in the observation area above her evaluation. Lena messes up the exam the evaluation is suddenly interrupted by Invalids staging a protest.

Lena goes in for an evaluation, during which she will undergo an oral exam and will be assigned a mate by the government.

Before they are cured, Lena and Hana, her best friend, plan to spend the summer together. In this world, falling in love is considered a disease. The procedure will actually prevent her from ever falling in love. Lena is waiting for her birthday, when she will be given a procedure that will remove all of her pain. There are rumoured to be people called “Invalids”living out there who have refused to be “cured.” The government, however, denies these people exist. “Out” is called the Wilds, the areas in between the cities and outside of civilization. No one is ever allowed in and no one is ever allowed out. As the story begins, seventeen-year-old Lena lives in Portland, Maine, which, like all other US cities, is surrounded by guards and electric fences to bar passage. Later on, Fox declined to pick up the pilot instead, it was picked up by Hulu and made available for streaming for a limited time in 2014. Emma Roberts was cast as one of the main characters,the writers and executive producers were chosen and began work. An adaptation into a television show was planned Fox ordered a pilot to be made. Delirium was a New York Times bestseller, and received largely favourable reviews. Another book, Alex, was also released between the first and second books. Oliver wrote several other books, two set between the first and second book, and another set between the second and third book, which were later compiled into one book, Delirium Stories: Hana, Annabel, and Raven. The novel is the first installment in a trilogy, the second being Pandemonium and the third, Requiem. Watching a news report about a pandemic, the two ideas combined to form Delirium. As her first book was about death, love was the next logical step. Oliver says she was inspired to write a novel about love after reading an essay by Gabriel Garcia Marquez, who said that all books were either about love or death. Delirium, Lauren Oliver’s dystopian young adult novel, was published in 2011 by Harper Collins.

Pandemonium delirium trilogy