Captain America: Injected with a super-soldier formula during World War II, Steve Rogers used his enhanced strength and agility to fight for the Allies until his plane crashed in the Arctic Ocean and he was frozen in the ice. Thawed out 70 years later, he was asked to serve his country once again as part of the Avenger Initiative.

Thor: Banished to Midgard (Earth) for his recklessness, the hammer-wielding God of Thunder returned to his home of Asgard to protect it from the machinations of his adopted brother Loki. Believed dead, Loki's re-appearance on Earth bodes ill for humanity, and Thor joins the Avengers to stop his nefarious plan.