The other short story that competes with "The Necklace" for the title of "Maupassant's masterpiece" is his first published story, "Boule de suif" (1880). Based on Maupassant's experiences as a soldier during the Franco-Prussian War, the story depicts the ravages of war on society and illustrates the hypocrisy of patriotism.
Another of Maupassant's stories, "The Jewels" (‘‘Les bijoux,’’ 1883), offers a plot that is the reverse of that of "The Necklace," with a character discovering that his deceased wife's supposedly imitation jewelry is in fact real.
The American novelist and critic Henry James who considered Maupassant's story a "little perfection," wrote a short story entitled "Paste'' based on "The Necklace." Its plot is remarkably similar to that of "The Jewels."
Gustave Flaubert's 1857 novel Madame Bovary, originally condemned as obscene, is today recognized as one of the classic novels of nineteenth-century French literature. Not only was Flaubert Maupassant's mentor, but there are also certain interesting parallels between the novel's title character and Madame Loisel.
Francis Steegmuller's Maupassant: A Lion in the Path, published in 1949, presents a good overview of Maupassant's life, his career as a writer, and his relationship with Flaubert.
For another example of the surprise ending by one of Maupassant's contemporaries, read "The Gift of the Magi" by O. Henry. It was collected in his 1906 book The Four Million and has been reprinted many times since.
In his 1819 poem "Ode on a Grecian Urn," John Keats examined the relationship between truth and beauty. His conclusion contrasts markedly with Maupassant's.