Rick Riordan gives us a short story of one encounter, and maybe a hint of future stories to come. Or else he's just being a nasty tease, laying the groundwork for two of his heroes from two different stories -- and two different mythologies and cultures -- coming together. And then not DOING anything with it! (Please, don't be cruel!
Carter from the Kane Chronicles is hunting a giant crocodile before it causes harm to innocent bystanders. He runs into Percy Jackson from the Percy Jackson and the Olympians and Heroes of Olympus books, who is doing the same. Since neither side knows that the gods from Greece and Egypt seem to be co-existing in our modern world, they seem to be speaking two different languages, rather than ordinary English ... and that kind of handicaps them in fighting the nasty old croc.
They conclude that someone is out to foment trouble between Greece and Egypt ... but who? I hope Riordan does follow through -- at least with more short stories, if not full-length books.