S7E13 - The Adventure of the Priory School, Part 3

It's a new day, and Holmes has at last pieced together all of the clues leading to the truth behind the disappearance of the Duke of Holdernesse's son, and the murder of the German teacher Heidegger. But as Holmes reveals his reasoning to the Duke, there's one final piece of the puzzle that catches even the great Sherlock Holmes by surprise. There's more here than meets the eye, and Sherlock Holmes is the only one who can put it all together. As he does, let the conclusion of his latest case help you conclude your own day and drift...