cunning

“Your native shrewdness, my dear Watson, that innate cunning which is the delight of your friends, would surely prevent you from inclosing cipher and message in the same envelope.

“The cunning dog has covered his tracks,” said he.

His brain is as cunning as his fingers, and though we meet signs of him at every turn, we never know where to find the man himself.

“He is very old and very cunning.