I've been trying to think of some way these three books are connected besides just simply being science fiction. The best I have come up with is the fact that in all three books, the main characters' parents have been killed in a terrible way. The Forest of Hands and Teeth along with The Knife of Never Letting Go have many similiarities; Leviathan is the odd story from this set. All of these books are also the first books of a series.
In the book The Forest of Hands and Teeth, by Carrie Ryan, Mary is the main character. Her father has already been taken into the forest, we as a reader are not told how. Her mother sits at the fence looking for her husband. The fence separates the village from the unconsecrated that linger there searching out live human flesh. A virus has spread across the world and once bitten by an unconsecrated, it means death or you become this terrible zombie like creature. Her mother is soon bitten and Mary blames herself for leaving her mother by herself. Her brother Jed also blames her and sends her to live with the Sisters at the Cathedral. The Sisters have many secrets. Mary longs to see the ocean. Her mother once told her stories of the ocean. The Sisters tell her not to dream of leaving but that she should marry and have children with her childhood friend Harry. She wishes that it was Travis, Harry's brother, that would come to take her into marriage. The fence becomes broken and a newly unconsecrated named Gabriel, also known as the fast one, is too much for the Guardians of the fence. Soon the entire village is in danger and Mary, Travis, Harry, Cass, Jed, Jed's wife Beth and a young orphan, Jacob are cut off from the village to wander the path. The fenced in path winds through the forest and provides some safety and provisions as this group tries to find another village or as Mary hopes, the ocean. Death is a certain thing as this group travels.
In a similiar book, The Knife of Never Letting Go, by Patrick Ness, Todd has been raised by two men on a farm in Prentisstown. His parents died when he was very young and he barely remembers them. As in The Forest of Hands and Teeth, it is the future and a virus has spread across the world. The virus in this case has made it possible for men to read each other's thoughts. Women can also read these thoughts but men can not read their's. Todd was told that the virus is the reason that there are no women left in Prentisstown. Todd is almost 13 and then he will be a man. Prentisstown has been waiting for this day as Todd is the last boy left in town to be turned to a man. But one day as Todd is walking through the swamp outside his farm, he hears a quiet, there is no noise like what he usually hears from all the men. When his noise tells Prentisstown about the quiet, the men come to talk to Todd about this. He is forced to run but he is given a good knife and a journal that his mother wrote before she died. Inside this book there is also a map and Todd is told where he should go. He takes along his faithful dog Manchee and head towards the swamp. There they meet the first girl Todd has ever seen, Viola. She is the cause of the quiet. She herself is quiet and will not answer Todd's questions. They travel together slowly becoming more than just travel companions. Soon there is a Prentisstown army after them. Todd tries to figure out why these men are so intent on capturing him or is it Viola that they want. And what does this have to do with him becoming a man in just a few days?
Leviathan is a little different from these other two books. It starts out again with Aleksander's parents being poisoned and killed. His parents are the Duke and Princess of Austro-Hungarian. The time period is set during World War I. There has been an emergency plan in place in case this was to happen. Alek is swept away in the middle of the night to save his life. He along with two tutors and two guard's in his father's army are sent running from the Germans in an effort to protect the throne. They escape in what is called a Stormwalker. This is a futuristic invention much like a tank but it walks or runs on two legs. This is the side of the Clankers. On the other side of the war, the Darwinists have strange futuristic inventions as well. The Darwinists have fabricated animals such as talking lizards and flying whales. Deryn is a young girl that dreams of flying but only boys (men) are allowed to join. She pretends to be a boy and soon finds herself on the Leviathan,a flying airship made up of a whale. The Leviathan must make it to the Ottoman Empire where it's precious cargo can be unloaded.
I guess these three books have something else in common. In all three books, the main characters are being chased,