Sherlock: 10 Ingenious Pieces Of Foreshadowing You Never Noticed

8. The Telegram From "CAM"

There were clues that Mary wasn't who she said she was; she recognised a skip code, and she had a great memory. But that didn't necessarily add up to the answer we were given about her did it? There was one more clue that wasn't actually alluded to in the show, but seems obvious now. As Sherlock, bored by the telegrams, read out the well wishes of everyone who couldn't be at the wedding, John and Mary smiled in recognition of their friends. And then Sherlock got to one telegram that made Mary look rather uncomfortable: "...Oodles of love and heaps of good wishes from CAM. Wish your family could have seen this." On first viewing, it seems like Mary's just upset about her family being mentioned. But given her connection to CAM, or Charles Augustus Magnussen, there's obviously more to it than that. It's a subtle clue to the following episode, and one that a few eagle-eyed fans picked up on; would we ever have guessed that Mary was in fact a top assassin though?