Typical of O. Henry's stories that end with an ironic twist, "One Thousand Dollars" has an ending that is both ironic and sentimental. Here is the sequence of events in O. Henry's narrative:
1. Lawyer Tolman informs Bobby Gillian that his wealthy uncle has bequeathed to him one thousand dollars. Further, Tolman tells him,
"you are required to render to us an account of the expenditure of this $1000.00 as soon as you have disposed of it."
2. Gillian cannot decide how to spend this money as it is what he calls "a confoundedly awkward amount." So, he goes to his club and talks to a "sequestered" and sarcastic friend, Old Bryson.
3. Bryson sardonically suggests several ideas, one of which is that he buy a chorus girl named Miss Lotta Lauriere a diamond necklace for this amount and then move to Idaho and raise sheep.
4. Gillian departs the club and takes a ride in a cab; he asks the cab driver what he would do with the money; then, after getting out of the cab, he asks a blind man.
5. Evidently, an idea comes into Gillian's mind and he returns to the cab, ordering the driver to take him to the law offices of Tolman & Sharp where he inquires about a Miss Hayden, a ward of his late uncle and her inheritance. He is told that she received only $10.00 and a ring.
6. Returning to the cab, Gillian gives the driver the address of his late uncle. Once there, he finds Miss Hayden, dressed in black, writing letters in the library. Gillian tells her that his uncle had a codicil which left her $1000.00. Blanching, she exclaims, "Oh! Oh!" In a low voice, Gillian adds, "I suppose...that you know I love you." Taking up the money, Miss Hayden merely replies, "I am sorry."
7. Gillian then writes a memorandum that reads,
Paid by the black sheep, Robert Gillian, $1000.00 on account of the eternal happiness, owed by Heaven to the best and dearest woman on earth
and returns to the law offices.
8. When he informs the lawyers that he has spent the money and has a memorandum, they "explored the caverns of an immense safe" and produce a codicil to the uncle's will which bequeaths Gillian $50,000.00 if he has spent the $1000.00 unselfishly. Otherwise, the sum is to go to Miss Hayden.
9. As Tolman reaches for Gillian's account, the young man snatches it up and tears it to pieces. He tells the lawyer, "I lost the thousand dollars on the races. Good-day to you gentlemen."
10. Tolman and Sharp shakes their heads mournfully, believing Gillian has continued what his uncle called "reprehensible dissipation," but Gillian leaves whistling, happy in his act of love.