Personally I'm just hoping this series is as good as the Vespers series. The Vesper series will be hard to top. It was the PERFECT sequel to series one and did exactly what a sequel should. The 3rd movie/book/book series often falls short of the orginal two (Exceptions like Return of The King,The Dark Knight Rises, and The Power of Three series exist) like Spiderman 3 and The Hunger Games: Mockingjay.
If I read correctly, J. Rutherford Pierce and his family drank part of the cahill serum. Its possible that Pierce himself drank the Lucian and Tomas serum since he displays superb strategy skills and high athletism. His wife, Debi Ann and his daughter, Cara may have drunk the Janus serum because Debi was rearranging her collection and Cara was fluently playing the violin. His son, Galt, may have drank the Tomas serum because he was playing tennis without "breaking a sweat". There is no indication of any of them drinking the Ekaterina serum. Besides, on card 301, it was said that the vespers are keeping tabs on Pierce, because he knows too much.
interesting ideas! i do think that this has to do with the lost city of atlantis. although there is no mention of the cahill serum, that can be possible, but then that will have some holes, such as how they got the serum etc. it is also possible that it is related to some sort of art piece, as series one was blue (the clue hunt) series two was red (the vespers were devious and cunning) and now series three is green, which might have something to do with the Janus.
I think Pierce most likely drank the full serum, due to his athleticism(Tomas), cunning plan(Lucian) and for Ekat, he was able to comprehend all that information in his office in a matter of seconds, and for Janus, uh... I guess maybe with the whole media thing (shrugs). His wife, no idea, I do think you're right with Janus; Cara, obviously Janus; Galt, definitely Tomas and possibly Lucian, due to "killer instinct."
Major Spoilers, do not read unless you read all books (Mainly Day of Doom and Shatterproof)
The Vespers? I figured their reputation to be active was damged severely due to the destruction of the Doomsday Device, the death of V1, unloyal members (Casper, an Cheyenne Wyoming, Sinead Starling, and Isabel Kabra), and loyal members either dead (no true proof Luna Amato was truly loyal, but Jonah had shot her) or arrested (Sandy Bancroft was arrested).
Or I would of believed they were no longer active and their reputation to compete with the Cahills for the true title "Greatest Family (or clan) ever", of course they had their flaws, as they would "Sell each other out" (Atticus said that) and that really proved them weak causing their defeat.
What do you think?