I think Echo's slash Caroline's former boyfriend is Alpha. They seem to have a super strong bond, and we've already seen, via Victor and Sierra's connection, that love can cause the dolls to go against protocol. Plus, in a spoiler I read earlier this month, I found out that we will be informally introduced to Alpha before we are formally introduced to him.
During last night's episode, Topher was trying to describe how unhelpful and annoying his boss was being, and she genuinely--and without skipping a beat--offered: "Sarcastic? Unfeeling? British?" I thought it was hilarious, until I realized it was a by-product of the drug that was infecting everyone. That seemed terrifying until I realized that because it didn't affect dolls the same way, it would help viewers determine if there were any more secret dolls around. We now know for a fact that Boyd, Ms. Dewitt, Topher and Agent Dominic aren't dolls. Damn! I wish the doc would've been there. I totally suspect her of being one. Or of at least being a traitor.
We also learned that the dolls are only recruited for 5 years, so it isn't entirely true that their memories are wiped out. I thought that it was going to be revealed that their memories were downloaded and saved somewhere, but since Echo can recall things, it's obvious that her memories are just placed on a backburner.
Can't wait till next week when all of the dolls (or most of them) revolt. It's about to get (more) interesting!