Microphones

Tom had the idea to use microphones with an amp before he thought of the birds in a box. He actually found the birds in a box when he went on a supply run around the block they were living on. Malorie thought of his idea after the children were born and took Cheryl's car to get them. Ever since that day in the book, she had them set up so everything outside was amplified. This, of course, was when the birds were no longer there.

Tom

Tom had a wife and a little girl named Robin. Robin was in eighth grade and was really smart for her age but she looked outside and Tom had found her in the bathtub with her wrists slit. He buried her in the backyard and later found George's house, which he, Don, and George resided and thought of solutions to this problem which was originally called the "Russia Report". George had the idea of looking at them indirectly which he later found out was not a solution at all. In the movie, Tom had survived with Malorie and the children but in the book, he died when all of the other housemates died. Leaving Malorie to fend for herself and the children.

Tom and Malorie

The movie shows Tom and Malorie in a relationship. But the book suggests that Malorie is the only one who has feelings for Tom. She longs for him, his voice, and his presence. But Tom is more concerned with being the leader of the house, although he has a kind tone towards Malorie.

Gore

The book has way more gore than the movie, which is completely understandable why it didn't make the cut. There are scenes of the housemates blindly stepping on and running over dead bodies, finding dead bodies of families, and even found someone, dead, who had scooped their eyes out into a bowl on the table. The book also tells about news reports like a pair of old-lady twins who where biting people's faces off at a hospital that were shot by the police. Plus, the death scenes in the book were different from the movie, most likely because they are impossible and needed to been more real than what they were.

Deaths

Shannon: She did not flip a car with a very pregnant Malorie in the passenger seat. Her and Malorie had been living in a house with blankets over the windows and while Malorie was downstairs watching the news, she called for Shannon who did not give a response. She walked upstairs to find Shannon had stabbed herself in the chest with a pair of scissors.

George: Although George did die watching the recording of the creatures, he did not bang his head on the floor. Instead, he tore his body through the rope that tied him to the chair and the book describes it as flesh ribbons.

The Housemates: All except Malorie died when Don removed the blankets from the windows and opened the doors.

Olympia: Although she did jump out of the attic window after giving birth, in the book, she hangs herself by her umbilical cord that she chewed off.

Gary

The pictures that can be seen spread across the table are actually just notes in the book. Malorie steals Gary's briefcase that he brought with him and finds it. It had his ideas written in it stating that he believed people's reactions to the creatures were psychosomatic meaning that the insanity that follows from looking at them aren't the creatures but the result of dramatic people looking at them. He doesn't believe that the creatures make people go insane, they choose to go insane. The housemates cast him out after Malorie tells them about the journal but Don sneaked him to the cellar where he lived for about seven weeks, in solitude, feeding Don his philosophies. It was Don who originally pulled the blankets down and opened the doors, not Gary. However, Gary did enable this behavior.

Victor

If you've read the book, this is probably the saddest part of it all. Victor is Jules' border collie who was locked in the cellar when the blankets were torn down. He survived with Malorie and went to the bar with her to fetch the microphones as her seeing eye dog. Except he saw a creature and it was then that Malorie knew animals were not immune. She listened as he snapped at the air and chewed off his leg. She had to leave him, she didn't have a choice.

Jane Tucker School For the Blind

The safe haven Malorie and the children go to in the end, is a school for the blind. However, a lot of the residents had gouged their eyes out because it was the ultimate protection. Because they do not resort to this method, Malorie stays.

Supply Runs

There were two supply runs that only consisted of Tom and Jules, not everyone. They found two huskies as seeing eye dogs and the bird box on the first run and the second run is when they went to the grocery store.

The Man on The River

I think the purpose of this man is simply to make Malorie uneasy. He originally had a motorized boat and tried to convince Malorie to remove her blind fold and even got really close to the boat, but Malorie rowed away then got attacked by a pack of wolves.