Netflix's original film Bird Box is a bona fide cultural phenomenon. Based on the equally successful book of the same name by Josh Malerman, the movie - which stars Sandra Bullock, Sarah Paulson, Trevante Rhodes, and John Malkovich - has spurred numerous memes, fan theories, and an ill-advised blindfolded "challenge."
The post-apocalyptic film centers on Malorie, who must shepherd her two kids down a dangerous river toward a sanctuary with enough food and supplies to last them several years. She must do so completely blindfolded, as there are creatures lurking about that, if looked at, can drive a person mad. The story also features flashbacks to five years prior, detailing Malorie and a band of other survivors' attempts at learning as much as they can about the monsters causing chaos outside their walls.
Malerman's novel follows much the same narrative path, though there are several scenes within the pages that were too intense for the adaptation.
We don't see much of Boy and Girl's infancy in the film version of Bird Box - they are born, and then the narrative jumps ahead five years, revealing that Tom and Malorie have been raising the children in seclusion. In Josh Malerman's novel, however, Tom perishes in the house after Don - acting on Gary's orders - lets the monsters in, leaving Malorie to raise the children on her own.
The horror of bringing up two children in this post-apocalyptic nightmare is palpable, and Malorie finds value in a harsh bit of advice she received from Don early in her pregnancy: she should forcibly remove the children's eyesight to ensure their safety.
Malorie nearly follows through, grabbing a can of paint thinner she knows will damage Girl's eyes.
All we learn about Tom in Netflix's Bird Box is that he's a veteran of the conflict in Iraq, he worked construction before the apocalypse, and he had experience with kids via his sister, who had three children and a fourth on the way.
In Josh Malerman's novel, however, Tom's backstory is a bit different. He tells Malorie he had a daughter who, even at her young age, saw the world wasn't "fair" and became increasingly despondent with the apocalypse looming outside their covered windows. Then one morning, Tom woke to a terrible sight.
In the film, Greg volunteers to be tied to a chair and watch security camera footage to see if he can look at one of the creatures via "pixels and heat" and not succumb to the madness. Greg discovers that seeing moving pictures of the monsters has the same effect as facing them in person. He loses his mind, rocks his chair to the ground, and clocks his head on a table.
This scene, as written by Josh Malerman, plays out much differently - and far grislier. Greg is called George in the novel, and we learn his fate from Tom, who tells the newly arrived Malorie what happened to the home's owner.
Olympia gives birth to Girl, whom Malorie raises as her own following Olympia's passing during the chaos unleashed by Don and Gary. In both the film and the book, Olympia jumps out the attic window after seeing one of the creatures.
Josh Malerman, however, includes an additional and far grimmer detail.