His personal experiences notwithstanding, O. Henry staunchly exhibits in his stories an affirmation of the conviction that people are essentially good and altruistic. Then, too, he concludes his stories with the surprise ending. So, with these two elements being essential to O. Henry's "The Last Leaf," an alternate ending needs to maintain the idea of personal sacrifice for another with a twist to the conclusion.
Certainly, O. Henry's ending is difficult to surpass. Perhaps, a variation of this denouement can be created in order to fulfill the assignment. For example, the ailing Johnsy could be rushed to a hospital during the night and placed in an oxygen tent. Although prohibited from entering her room, Sue and old Behrman manage together to gain entry to the room (Sue could commandeer a nurse's white outfit and roll Behrman down the hall as though he were a patient). Sue, then, acts as though she is assigned to check on Johnsy and slips Behrman into the room where he paints a green, beautifully delicate, leaf onto the clear walls of the oxygen tent. In a fog of delirium, Johnsy perceives the leaf that Behrman has painted and in her delusionary state believes she is home, looking out the window. She falls back into a deep sleep, only becoming conscious enough to occasionally see the leaf. "The last leaf has survived! I must, too," she dreams. At last, Johnsy gains enough strength and becomes conscious.
When the doctor enters and perceives the solitary leaf painted on her tent, he is astounded. But, Johnsy, still groggy,"explains." The physician patronizes her, agreeing to what she says in the hope that she will regain strength. At last, Sue and Behrman are admitted and Johnsy tells them of her dreams and how she awoke to see the delicate leaf, and she realized,
"Something has made that last leaf stay there to show me how wicked I was."
As she then closes her eyes and drifts into sleep, Sue and Behrman smile over her.