Role in the film
The Polar Express stops in front of Billy's house one Christmas Eve, much to the surprise of Know-It-All, who thought Hero Boy was supposed to be the last one picked up. The Conductor invites him to get on, but Billy declines. However, he quickly changes his mind and decides to get on, but the train was moving too fast for him to catch up, so Hero Boy, under a suggestion by Know-It-All, pulls the emergency brake, which brings the train to a complete stop, allowing Billy to get on the train. However, he decides to sit in the observation car away from the other children.
Due to being in a separate coach, Billy was not served any hot chocolate like all the other children, but Hero Girl has saved a cup for him and, accompanied with the Conductor, goes to the other car to give it to him. Later, when Hero Boy is trying to return Hero Girl's ticket, he tries asking Billy where she and the Conductor went, after which he looks up at the window where Hero Boy sees their shadow and goes to climb to the roof of the locomotive.
The Conductor must have punched Billy's ticket sometime during the trip, but there is no scene in the film in which this happens. It can be seen, however, that the word "ON" was punched.
Later, after the train passes by the herd of caribou, goes down Glacier Gulch and crosses the Ice Lake and Hero Boy, Hero Girl and the Conductor get back to the coaches, Hero Boy and Hero Girl find Billy looking out from the back of the train, singing "When Christmas Comes to Town," which Hero Girl eventually joins in. After that, they watch the Northern Lights form in the sky while the Conductor comes by to inform them that they have crossed the Arctic Circle. He then points at some lights in the distance and says that it is the North Pole.
The train soon stops at the North Pole center and the Conductor and all the children get off. However, Hero Boy and Hero Girl notice Billy staying behind. The Conductor tells them he is not required to come, but Hero Boy and Hero Girl decide to go and convince him to come. Billy tells them that Christmas has never worked out for him. Suddenly, due to Hero Boy having accidentally uncoupled it from the rest of the train, the coach begins rolling away and becoming a runaway down a steep hill. He manages to stop it, however, by turning the coach's brake wheel right before it crashes off of the turntable. The children get off of the coach and go to find their way to the center by following the sounds of the silver bells, but only Hero Girl and Billy could hear it.
Along the way, they pass through a communications room where a few elves are doing some last minute work. After they finish, they take the pneumatic to the center. The children decide to take use pneumatic too, but it takes them to a wrapping room instead. At the wrapping room, the children find a present that is addressed to Billy. Billy decides to follow it and Hero Boy and Hero Girl follow him. They end up on a big slide, which takes them to a large pile of presents. Billy is excited to find out what his present is, thinking he knows what it is and that it is something he wanted for a long time, but Hero Boy and Hero Girl tell him not to open it due to a note saying, "Do not open until Christmas." The presents are then enclosed in a big red bag, which is lifted by a pair of zeppelins and carried to the center. Along the way, something suddenly gets a hold of Billy's leg, but he is freed after Hero Boy and Hero Girl pull on his arm. It turns out to be Know-It-All, who was in the pile of presents figuring out what he is getting for Christmas.
Soon, they arrive at the North Pole center and the elves help the children out of the bag. At first, Billy is hesitant to leave his present in the bag until the elves assure him it will be in good hands. Later, Santa Claus shows up and speaks with the children. He congratulates Billy for having made new friends and says that friendship is the best gift of all. Billy also watches Hero Boy being given the first gift of Christmas and Santa Claus flying off to deliver his presents. After that, when the children get back on the train, the Conductor punches Billy's ticket again. It reads "DEPEND ON" when he first looks at it, but it changes to "RELY ON" when he flips it and then "COUNT ON" when he flips it again. The Conductor called the ticket, "Some special ticket." Billy is also one of the children who want to see Hero Boy's bell. He also suggests they go outside to look for it after finding out he lost it, but the train was already on its way.
Later, the train stops in front of Billy's house to let him get off. At first, Know-It-All questions where he is going before Billy tells him the train has stopped at his house. He also thanks Hero Boy for stopping the train for him. He then gets off the train and runs back to his house where he finds his present. Just as the train was leaving, he goes outside with it and calls out to Hero Boy and Hero Girl that Santa has been to his house.
It is never revealed in the film what Billy's present actually was.
- "My name is Billy!"
- Billy is one of many characters in the film to not have been from the book.
- Billy is the only child on the train, and one of few characters in the film, to be identified by name.
- Billy's address, 11344 Edbrooke Avenue, is the real life address of the childhood home of Robert Zemeckis, the director of the film. The house is in the south side of Roseland, a neighborhood in southern Chicago. The real Grand Rapids, Michigan does not have a street called Edbrooke Avenue, though.
- Billy is only referred to as "Lonely Boy" in the credits.
- Billy is one of five characters in the movie to have an actual name, the others being Santa Claus, Sarah, and Smokey and Steamer (although the latter two’s names are only revealed during the end credits.)