Among the superhero team comics, the Avengers were usually my favorite, the all-star team of the Marvel Universe. The issues covered in Essential Avengers Volume 8 not only represent some of the earliest issues I'd read during their first release, but also the comic at the top of its game.
What makes this volume so good? To start with, it's got lots of big villains: Thanos, Ultron, the Absorbing Man, Count Nefaria and Korvac. It's also got some of Marvel's best 1970s-1980s talent: George Perez, John Byrne and Jim Starlin, along with other big names like Jim Shooter, Sal Buscema and Carmen Infantino.
While contending with the bad guys, the Avengers also have to deal with Henry Gyrich, a government agent who finds the team to be rather lax with their security. As a result, he's stripped away their government access. It will be restored, but at a price: Gyrich gets to dictate who's on the Avengers. It's not a popular decision: as Iron Man asks, "Just who the hell do you think you are?", Gyrich coolly retorts, "I'm the Government, mister."
Gyrich's efforts would have a long term impact on the Avengers, as the core team would stick with only seven members, the amount that Gyrich allowed. It would also be one of the first real attempts at government oversight of the superheroes, something that would continue for many years, culminating in the events of Civil War.
That's far in the future for these comics. Suffice it to say that this is one of the top volumes in the Essentials series; for those just being introduced to the team through the movie, this will a nice set: reasonably self-contained and with all the heroes of the movie appearing except the Hulk.