The title of this episode "Miss Understood" continues a naming convention started in S4E7, "Miss Taken (2016)", where the character of Mina Davenport/Cassie is first introduced.
While focusing on the main case, Sherlock spends a few minutes summarizing a case involving a man named Garrideb, who is being taken back to England for trial. Like other short case summaries in Elementary, this is based on an original Sir Arthur Conan Doyle short story: "The Adventure of the Three Garridebs." In the story, published in 1924, Nathan Garrideb is targeted by an man claiming to be John Garrideb. He supposedly needs three people named Garrideb to split an inheritance. John sends Nathan to meet Howard Garrideb, meanwhile breaking into Nathan's house to find something left there by the previous owner, a criminal.