The latest round of Holmes brothers bickering finally turns into an actual physical fight. (Ridiculously advanced martial arts techniques, all-out brawling and/or childish playground tactics? You decide!) Mycroft eventually wins with some kind of classic big brother move like getting Sherlock in a headlock.

Bonus points for the two of them only belatedly remembering/noticing they have a staring audience and ending up laughing together for the first time in years.