Fogg, a pompous and self-important man, is convinced the necklace is hidden in the house of the wealthy Mrs. Van Dusen. Tuttle, a more timid and gullible soul, goes along with his friend's theories.
Their investigation involves a series of comical misunderstandings and misinterpretations. They misidentify Mrs. Van Dusen's servants, believe a dog is the culprit, and even end up hiding in a closet, mistaking a laundry chute for a secret passage.
Ultimately, their efforts prove futile, and they are forced to admit defeat. The true culprit is revealed to be Mrs. Van Dusen's nephew, who simply took the necklace for a prank.
The story is a satirical look at the overblown nature of detective fiction and the often-absurd lengths to which amateurs will go in their pursuit of solving mysteries. It highlights the humor in human vanity and the tendency to see conspiracies where none exist.