Earth-199999. Modern day, 21st century. A secret organization called S.H.I.E.L.D. works for the US government, employing advanced, state of the art technology to counter the threats the world faces. Superheroes, such as the brilliant inventor Tony Stark or the supersoldier Captain America, are quite real, but supervillains exist as well, most notably Loki of Asgard, but also the Red Skull and the Chitauri.
And war is upon mankind.
In a bid for power, Loki has opened a portal to another galaxy, allowing the Chitauri through in order to conquer Earth. Though the Chitauri find themselves unable to conquer the planet... humanity struggles to keep this from changing, and the Earth will need its mightiest heroes to assemble if they want a chance to win.
OOC Info: This themelisting includes ONLY heroes and villains portrayed in the Earth-199999 movie universe. If it's NOT in a movie yet, it CANNOT be applied for in this themelisting. Iron Man, Iron Man 2, Thor, The Incredible Hulk and Captain America: The First Avenger are all considered to have happened already. The Avengers has partially happened. Loki has succesfully opened a portal, but was pushed back. Earth is now in a full-out war with the Chitauri, with Loki at their command. If in doubt, please talk with a member of the cast before applying in this themelisting.