Avengers

The team was assembled to answer a competitor. DC had put its heroes together in one comic and it sold, so Marvel gathered its own in September 1963 and let the line-up change constantly. That instability is the whole idea, and it is what the screen adaptations keep removing.

1963: Marvel builds a team it can rebuild every year

Stan Lee and Jack Kirby put Thor, Iron Man, Hulk, Ant-Man and the Wasp in one comic. Hulk left after two issues.

By the sixteenth issue the founders had gone and been replaced by three former villains. No other team comic had done that, and it became the series' method: the roster is a variable, not a premise.

The comic could therefore absorb whoever Marvel needed to promote, which is why more than two hundred characters have been Avengers at some point. The book has run almost continuously for sixty years on that principle.

Three animated series, three cancellations for outside reasons

Avengers: United They Stand arrived in 1999 and put the characters in armour because the toy line required vehicles. It also left out Iron Man and Captain America, who had their own shows. It lasted thirteen episodes.

The Avengers: Earth's Mightiest Heroes in 2010 is the adaptation comics readers rate highest: 52 episodes, built on the classic storylines. It was cancelled after two seasons.

Avengers Assemble replaced it in 2013 with a cast matching the films. The reason given at the time was alignment with the cinema line-up, and it is the clearest case of a good adaptation removed for reasons unrelated to its quality.

Two billion dollars for the film that kills half the cast

Avengers: Infinity War took more than two billion dollars in 2018 and ends with its heroes losing. That was possible only because ten years of separate films had already established every character.

No studio had attempted that structure. Twenty-two films arriving in sequence, each partly a set-up for a crossover, is a distribution model rather than a narrative one.

Every studio then tried to copy it. Universal, Sony, Warner and Paramount all announced connected universes between 2014 and 2017, and none of them completed the plan.

What a rotating roster made possible

Because the team changes, the comic can retire a character without ending. Captain America has left and returned repeatedly; the Avengers have been disbanded in the fiction at least four times.

That flexibility is also a commercial instrument: joining the team is how Marvel raises a minor character's profile, and it has been used that way since 1965.

The films inherited the concept and fixed the cast, which worked for a decade and then required the same solution the comic found in 1965: change the people.