In 1800's France there lived couple with the last name of loisel. They live a mediocre life in france but Madame Loisel isn't content with what she has. She thinks that she needs all the fancy things in life and desperately wants a better social life.
Madame Loisel lives a mediocre life but she wants things that she can't afford
After Monsieur got her tickets to the big party she needed a nice dress, so monsieur got her a dress but it wasn't good enough for her. She wanted a diamond necklace, so she asked one of her friends if she could borrow her necklace.
When Madame Loisel got home from the party she realized that her friends necklace was gone, and she couldn't find it anywhere.
They looked everywhere and couldn't find it. So they decided that they should go to a jeweler and make a diamond necklace that looks like that even though they didn't have the money to pay for it.
After that they worked for ten years to pay off that debt. She saw her friend in public and went up to her and told her that they actually lost the original necklace and that they had to work ten years to pay that off. Her friend laughed and said it was fake.