"Ugh--" Sherlock was about to comment on the unreliability and outright deception of some eyewitnesses when what Will said next caught him completely off guard.

He paused, his forked tongue flicking out and in, as if he was trying very hard to figure out if he was being made fun of or not. It wouldn't be the first time. He put his milkshake and chips down on the nearest table.

"Sorry, did you say brain-eating limb!?"