A victory by the team seems 'within the realm of possibility'. [=a victory seems possible]
It's not 'beyond the realm of possibility' [=it's not impossible] that he will return.
new discoveries in the 'realm' of medicine
(..) (YELLING) GUARD: Keep moving. Go ahead of me. Don't you turn around! Where do we go next? Hogun, the peace is nearly won across the Nine Realms. You should stay here. Be with your people, where your heart is. Asgard can wait. You have my thanks. As you have mine. (..)2013 Thor: The Dark World
(..) You'll make that witless oaf king while I rot in chains. Thor must strive to undo the damage you have done. He will bring order to the Nine Realms and then, yes... He will be king. (ALL CLAMORING) (GRUNTING) (GRUNTS) (..)2013 Thor: The Dark World