This is the slobberknocker that's been building up since the very first issue. Hulk has left the Avengers. He's now on the run and seems more out of control than ever. Even Rick Jones and the dreaded Teen Brigade can't get him to settle down. With the Hulk being a former team-mate (for one issue!) and all of that, the Earth's Mightiest Heroes feel it's up to them to get a hold of the beast and get him under control. So the first half of the issue focuses on the Avengers hunting down the green menace, until something unexpected happens: Hulk runs into Namor, the Sub-Mariner!
The Hulk/Namor team-up starts off in classic superhero team-up fashion: a fight. The two get into an epic brawl where both of their strenghts are clearly highlighted (Hulk is a monster on land while Namor can't be touched under the sea) and they eventually agree to join forces against the Avengers. The Hulk/Namor vs. Avengers showdown that ensues is really awesome and succesfully puts over the Sub-Mariner as a total badass.
Some of the characters' personality traits start being a little more defined too through all this action. Thor's warrior-personna comes through more agressively while Ironman thinks more logically and tries to keep his team-mate from using excessive force on the Hulk. Speaking of Shellhead, he's switched to the classic red and gold look in this one. Sadly, the armor still isn't up to snuff, as Namor neutralizes it with an "emery dust pellet". Ouch.
This issue also offers a boatload of cameos from Spiderman, the Fantastic Four and the X-Men to round up the best Avengers issue so far. Good stuff!