Trevor is an 11-year-old boy who comes up with the idea of "paying it forward" as a way to enact positive change in the world. He starts by helping three people - Jerry, a homeless man, by giving him money and a place to stay to get back on his feet; Mr. Simonet, by helping him go on a date and find confidence; and Adam, though Trevor is unable to fully help him. These people are then supposed to pay it forward by helping three people each, setting off a chain reaction of good deeds across the United States. Unfortunately, Trevor is fatally stabbed while trying to help Adam, but his message of paying it forward continues to spread.