I'm sure that by this point, a large percentage of you have seen The Avengers, and know how great it is. Its massive success pretty much guarantees a sequel, and there has already been plenty of speculation on where it might go. A big hint was dropped in the post-credits scene, in which we saw Thanos.

.But personally, I would rather see The Avengers fighting a more Earth-based threat in the second movie, rather than another alien invasion. So, here's what I have in mind:

The movie begins with Black Widow and Hawkeye investigating alleged HYDRA activity. The two infiltrate a HYDRA base and find HYDRA scientists creating a trans-dimensional portal of some kind. Black Widow and Hawkeye try to intervene but are unable to stop the portal from opening. And from it, a familiar figure emerges: the Red Skull. Hawkeye and Widow escape, and Widow calls Nick Fury to tell something like, "Its time to assemble."

The Avengers are gathered once again. At the SHIELD HQ, they are introduced to professor Hank Pym, who explains his theory that, when the Red Skull touched the tesseract in "Captain America," he was not killed. Rather, he was flung into a kind of stasis on the far end of the galaxy (and he survived because, you know, movie science). HYDRA was able to more or less replicate the tesseract energy, and bring the Red Skull back to Earth. This of course really bothers Captain America, who has long believed his enemy to be dead.

Bruce Banner and Hank Pym are able to track the residual tesseract energy signature left on the Red Skull, and the Avengers head to a HYDRA facility to stop them before their plans can even begin. However, the team quickly realizes they have walked into a trap. There is then a big battle against HYDRA forces, who have hired some mercenaries to assist them (Taskmaster, anyone!?). During the battle, Cap has a brief confrontation with the Red Skull, and the enemy is able to draw some of Hulk's blood. The Red Skull then sets the base to self-destruct, and HYDRA makes their escape. The Avengers barely get out of the base before it detonates. Back at the HQ, Iron Man points out that Cap made a few bad calls during the fight, and he wonders if Cap's grudge against the Red Skull is interfering with his judgement. This leads to a bit of a dispute between the two. And we get some character development for Hank Pym, too.

We then see a bit of HYDRA's plan, as they are using the Hulk DNA they extracted to create Hulk-like super soldiers. HYDRA forces, along with a handful of these soldiers, attack the Avengers head on. There's another big fight, but the attack proves to be nothing more than a distraction when Taskmaster infiltrates the SHIELD vault and steals none other than Loki's scepter (I don't think that was destroyed in The Avengers, but if I'm wrong please tell me). HYDRA forces retreat. The Avengers quickly notice the scepter is missing, and Thor begins to understand HYDRA's plan.

Red Skull uses the scepter, combined with HYDRA tech, to rip open a portal to Asgard. HYDRA then sends their army of Hulks into Asgard, launching a massive offensive strike. Hulk has already been shown to be a match for Thor in the cinematic universe, so an army of Hulk-like beings could easily do some damage in Asgard. Thor explains that HYDRA is after the Infinity Gauntlet, which was shown to be in Odin's vault in the "Thor" movie. After giving a brief explanation of what the gauntlet is capable of, the Avengers try to intervene but the portal closes before they can follow HYDRA to Asgard.

Hank Pym realizes, however, that the Hulk emits the same gamma radiation as the tesseract. So basically, they make Hulk as angry as they can, and Black Widow lures him into the HYDRA portal device, which draws the gamma radiation and briefly opens a second portal. The Avengers go to Asgard to find it in ruins, the Asgardians warring against the army of Hulks. There is, of course, a huge epic fight. During the battle, Cap and Iron Man wind up fighting Red Skull, wielding Loki's scepter. They destroy the scepter, but the HYDRA Hulks are able to break into Odin's vault and steal the Infinity Gauntlet.

Of course, the Avengers are able to find a way to stop HYDRA, and the Red Skull is left to be punished by the gods while the heroes return to Earth... with the Infinity Gauntlet, which is safely locked away in an impenetrable vault beneath Stark Tower.

This could lead into the third movie. Since the gauntlet is now on Earth, Thanos has a good reason to go there...

What do you guys think? Realistically, I know that this will never happen, but its fun to think about anyway.