I really loved The Eternal Ones (so happy to have won an advance copy from Penguin!!! Maybe they'll love me and I'll somehow get a copy of The Eternal Ones, too ;-)) - my review of it is here: r e v i e w
In case you'd like to read it, however, here it is:
Haven Moore and Iain Morrow have been living a blissful life in Rome, an ocean way from the Ouroboros Society and its diabolical leader. But paradise is not to last. The mysterious disappearance of Haven's best friend, Beau, sends the pair running back to New York, where they encounter the Horae, an underground group of women who have spent centuries scheming to destroy Adam Rosier. Only they can help Haven uncover the secret to Beau's whereabouts in one of her past lives. But their help comes at a price: Haven must infiltrate the Ouroboros Society, charm Adam Rosier, and lure him into a trap. It's a plan the Horae believe will save the world-but Haven and Iain fear that it may destroy the happiness they've been chasing for two thousand years.