Love and loyalty

How Conan Doyle explores love, friendship and loyalty, from Watson and Mary to Holmes and Watson and the oath of the Four across the text, and why it matters to the text's meaning.
Where it appears, the key quotations that show it, and different ways it can be interpreted.
Evidence from the beginning, middle and end of the text.
How to use the lesson's key quotations in an essay, with a short worked paragraph.
Key quotations: 'the sweet face of Mary Morstan looking down upon me', 'And two knight-errants to the rescue', 'I really cannot congratulate you', 'for we had sworn that we should each always act for all', 'The four of us must always act together', 'capable of forming most devoted friendships', 'Your presence will be of great service to me'.
Watson's growing love for Mary, the friendship of Holmes and Watson, and the oath that binds the Four.

What you need to know