From “A Study in Pink” to “The Reichenbach Fall,” watching John master his emotions. That’s when we see the depth of his feelings and his character, not when he breaks down, but when he shores himself up. Here’s a man tender enough to be a doctor and strong enough to be a soldier, with the power to hold those parts of his character in balance. Also one who’s been brought out of dark interior isolation to a place of greater light and connection: he’s in similar emotional states at the end, grieving the loss of fellow soldiers and soldiering on himself, but in very different social circumstances, with both Ella and Mrs. Hudson to help share his grief. Lovely parallel here, just lovely.