The Ricardo's eleventh wedding anniversary is approaching and Lucy finds herself dropping some none-to-subtle hints in Ricky's direction. Little does she realize that her husband has already made plans for the anniversary, having arranged to buy at a discount a string of pearls for Lucy through a neighbor, Grace Foster, who happens to work at Joseff Jewelry company.
But Ricky's many surreptitious trips to Grace's apartment (while Mr. Foster is out of town) to inspect the pearls have got Lucy suspecting the worst: Ricky is having an affair with Mrs. Foster.
When Lucy and Ethel overhear what's going on in Grace's apartment (2-A), using the snooper's friend (furnace pipes), they decide to don some discarded painters' overalls and make their way up a scaffold to spy on the "lovers."
Naturally, havoc follows when Lucy spies Ricky fondling Grace's neck. Finally, before surprising Lucy with the gift, Ricky pretends he is having a tryst with the Foster woman, then exclaims: "Grace and I have decided, these are the pearls I will give you for our wedding anniversary." Lucy is surprised and all is forgiven.
Special Notes: The Arnazes were married eleven years when this episode was filmed. Joseff Jewelry is a company, headquartered in Burbank, California, that supplies jewelry for movies and TV shows.