The first time I watched ASiB was with my husband, this was back in January this year. When the "beautiful woman" came to collect John to take him to see Irene, I assumed it was Anthea, but my husband (who is very good with faces) said it was a different actress. I was sure it was the same actress and suggested perhaps that her weight had changed (she was wearing a flowing outfit which covered her figure) and also her hair and makeup were different. My hubby insisted it was a completely different actress, so I had a look on IMdB. When I scrolled down through the cast list I came to Lisa McAllister, and sure enough it has her listed as "Anthea" in three episodes: A Study in Pink, A Scandal in Belgravia and The Empty Hearse. So I thought I was proven right, even though my husband still insisted otherwise.
So anyway, months later I am rewatching episodes, and I get to my third viewing of ASiB and for some reason I decide to investigate again. Somehow a google search turns up the answer, and I humbly showed my husband this page http://finalproblem.tumblr.com/post/19314255179/hi-well-done-on-your-blog-very-well-written-do so he could tell me "I told you so".
Here's Lisa McAllister as "Anthea" in A Study in Pink:
And here's Thomasina Rand credited as "Beautiful Woman" in A Scandal in Belgravia:
Really similar, right? At least I'm not the only one who fell for it
So apart from the other viewers who were tricked (like me), it's now obvious to me that John was meant to believe that it was Anthea too. The first time 'round, I didn't really think about the fact that the woman spoke into her phone saying "you were right, he thinks it's Mycroft", I just thought Irene (or even Mycroft himself for whatever reason) had arranged it, and that it was indeed Anthea. Now that I've seen that it's a different actress, I'm realising that Irene arranged for an Anthea look-alike so that John would go along with her thinking he was meeting Mycroft - but also because it's Irene's thing to "know what people like", and John likes Anthea. That was probably really obvious to everyone else, but I thought I would post this revelation anyway
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