It's not a complicated story–writer Roger Langridge sends Captain America (from World War II) and Thor (from the present day) back to Camelot. They discover Loki has wormed his way into King Arthur's court and there's some trouble.
Good thing there are a couple superheroes to deal with it.
Langridge doesn't worry about establishing the relationship between Cap and Thor, he moves right into Loki, the Knights of the Round Table and the adventure. He's got a lovely Empire Strikes Back homage going too for the heroes versus a three-headed dragon. You'll just have to read it.
At its core–with Chris Samnee on the art, doing a wonderful job–it's an issue of Thor: The Mighty Avenger with Cap (the Fighting Avenger version) thrown in. Langridge does make a little time for a Thor and Jane character development subplot and, while lovely, it begs for more.
So it's a functional success.
Once and Future Avengers!; writer, Roger Langridge; artist, Chris Samnee; colorist, Matthew Wilson; letterer, Rus Wooton; editors, Sana Amanat and Michael Horwitz; publisher, Marvel Comics.