And yet it would be the blackest treachery to Holmes to draw back now from the part which he had intrusted to me.
However that may be, the young lady was very decidedly carried away, and, having quite made up her mind that her stepfather was in France, the suspicion of treachery never for an instant entered her mind.
There are no more uses of "treachery" in the book.
Show samples from other sources
Benedict Arnold remains the U.S.’s symbol of ultimate treachery.
She was going to get an award for bravery when she should really be kicked out of the Smoke for treachery.