As in many O. Henry stories, the ending of “One Thousand Dollars” offers an ironic twist. Gillian is a frivolous man who depends on his uncle to finance his extravagant lifestyle. The reader expects this behavior will continue; however, O. Henry follows the evolution of Gillian’s character from a selfish beneficiary to a selfless benefactor. Instead of taking the fortune for himself, he directs it to Miss Hayden out of love, even though his love is unrequited.

We see evidence of Gillian’s character through his interactions with others and their perceptions of him. In the first scene, the solemn Tolman admonishes Gillian for his lack of attention, but Gillian responds jokingly. The same is true when Gillian meets with Bryson, who is annoyed by his presence. Bryson points out that the money could mean a lot or little, depending on who has it. He runs through morally grounded uses of the money, which offends Gillian, who notes that more people would like Bryson if he didn’t always moralize things. He again asks what he could do with the money, demonstrating that Bryson’s original suggestions were of no interest to him. This exchange shows that Gillian has been selfish to this point.