http://tvline.com/2015/11/05/arrow-who-dies-season-4-spoilers/
Question: I am dying to find out more about Sam’s visions this season on Supernatural. What can you tell us about that? —Elena M. Ausiello: Sam will be “exploring” his visions and “trying to figure out who’s talking to him and what they mean,” star Jensen Ackles previews. “So he takes it upon himself to go there without Dean, and it leaves me in the dust. Then, of course, Dean has to follow, [which leads to] some interesting alliances.”