Dr. Heidegger's Experiment Characters
All of the characters in Hawthorne's short story are advanced in age. Dr. Heidegger is described as "old" and the four people he invites to his study are described as "venerable." The men are "white-bearded." They are further described as "melancholy old creatures who had been unfortunate in life."
Mr. Medbourne is a man who had once been a successful merchant but had lost all his money and was nearly reduced to the status of a beggar.
Colonel Killigrew suffers from various health problems that developed as a result of his hedonism when he was a younger man.
Mr. Gascoigne has lapsed into obscurity after having been notorious for his evil deeds as a politician.
Widow Wycherly is a woman who had been somewhat promiscuous in her youth, and the upper class has turned its back on her. The three male guests of Dr. Heidegger had all vied for her attention when they were young.
Before he gives them the potion that will restore their youth, Dr. Heidegger, who has no desire to be younger, counsels them to remember the mistakes that had ruined their lives and to avoid falling into those same behaviors. All four dismiss him, vaguely insulted that he thinks they could be so cavalier about a second chance. But true to form, they all revert to youthful versions of themselves and repeat the thoughts and actions that compromised their reputations the first time around.