I got kind of curious of the guy who plays the eye-patched man (Sou). Not because I thought I saw him before (I really didn't get much good look at him during this episode), but I'd seen rumors about him possibly also playing Kabuto. At first I'd dismissed that, but then I think...that kind of makes sense. Mayu is obviously Hiyori/Jyuka replacement, though perhaps an improvement on both. (And, something not in the original series, Obaa-chan actually made an appearance.) Mayu seems to also be doing the grandmother said thing, so it would be weird if she's someone else's sister other than Souji (at least I hope there is a direct counterpart for Souji--there are ones for Arata and Sou after all). I know this is an AU and all, but really, if they are bothering to keep Souji's family (or clone family, as it is) they better keep Souji, too. (Not to mention Mayu thinking Kabuto's killed her brother is similar to Hiyori's feeling (I don't remember whom Hiyori thought Kabuto killed, though--got to find the episode(s) to re-watch).) And I believe the current speculation, too, that Sou is probably a worm who takes on Souji's appearance.
So, the main point is, I went clicking a bit and ended up finding out that the actor for Sou (Daijiro Kawaoka), is also in Detective Conan Drama 2. I was blanking a bit on which character he might have been. But then it came to me. I still haven't confirmed (because the name of the character he's playing means practically nothing to me as I tend to remember the role more than the name), but I think I'm right as to who he is: the guy who is the culprit). And that just makes me laugh. Seriously, though, I don't believe many people who have already been in dramas would come to play kamen riders.
To me, Decade continues to be very episodic, so much that I think I could have skipped around and just watched the worlds episodes in almost any order (two episodes of each world together, though). But I still hope to finish KR Hibiki before the series reaches that world.