Metacritic reviews

This is a movie that is almost exhaustingly large-scale, and Ultron's ultimate plan involves a crazy visual idea that Whedon makes sort of beautiful and eerie. It's got so much action that I'm going to bet some audiences go numb after a while. But in scene after scene, there are beats and stunts and poses that suggest that an army of comic book fanatics worked on this movie.

Bigger and, yes, darker than the first, this is less air-punchingly gleeful but probably more consistent. Thanks to Whedon and the most charismatic, compelling cast you’ll find anywhere, Age of Ultron redefines the scale we can expect from our superhero epics but still fits human-sized emotion amid the bombast.

The new movie is a sleeker, faster, funnier piece of work — the sort of sequel (like “Star Trek II: The Wrath of Khan,” “Superman II” and “Indiana Jones and the Temple of Doom” before it) that shrugs off the self-seriousness of its predecessor and fully embraces its inner Saturday-morning serial.

It’s all operatically mad, and the city-destroying final confrontation is becoming a bit familiar, but Whedon carries it off with such joy and even a kind of evangelism.

Part horror, part love story, part morality tale, Age Of Ultron is a smart superhero smackdown that raises the bar once more.

It’s the interplay between the film’s many different characters, rather than the blow-up-the-world crisis they’re trying to defuse, that keeps you on the edge of your seat.

It may well be that we’ll eventually stop looking at these Marvel films as discrete, individual experiences rather than chapters in an epic binge-watch, but even by those standards, Avengers: Age of Ultron feels like a solid but overstuffed episode, one more concerned with being connective tissue than anything else.

Whedon and his large, capable cast (even larger for this follow-up) deliver enough adventure, laughs and flat-out spectacle to ensure that audiences will feel as if they have gotten their money’s worth, especially when Ultron zeroes in on the quiet humanity beneath the special effects.

Avengers: Age of Ultron succeeds in the top priority of creating a worthy opponent for its superheroes and giving the latter a few new things to do, but this time the action scenes don't always measure up and some of the characters are left in a kind of dramatic no-man's-land.

Whedon has revealed that his first cut ran for well over three hours, and it shows: Ultron feels excessively nipped and tucked, barrelling from one explosive set-piece to the next, leaving ideas half-formed and character motivations murky.