Whedon borrowed the name only from the most recent popular comics story involving Ultron, a longtime foe of the Avengers. Book and film do borrow from a common source, however. James Cameron's Terminator has had an enduring influence on pop culture. The Age of Ultron graphic novel borrowed from it the idea of escapees from a dark future arriving in our time to change history for the better. For the movie, Whedon borrows the "Skynet" concept of artificial intelligence, designed to protect humanity, turning against it with genocidal intentions. Deviating from Ultron's comics origin -- his canonical creator, Dr. Henry Pym, won't make his movie debut until this summer's Ant-Man -- Whedon makes him a creation of Tony Stark and follows up on the preventative-measures-are-bad theme of Captain America: The Winter Soldier. Still traumatized from the Chitauri invasion, Stark wants a new line of defense against alien invaders and uses Chiaturi technology -- including a mysterious gem inside the much-handled weapon introduced in the first movie -- to speed up development. Captain America himself cautions that "Every attempt to win a war before it starts gets innocent people killed," and his sporadic disagreements with Stark seem meant to set up a more dramatic showdown in next year's Civil War. Predictably, Stark's creation turns against him, calculating that evolution alone will safeguard life on earth and can only be assured by orchestrating an extinction-level event. Ultron's unlikely allies are the twins Wanda and Pietro Maximoff, disgruntled Ruritanian orphans who volunteered for a Chitauri-powered Hydra mutation program to avenge themselves on Tony Stark, whose munitions killed their parents. The tinkering turns Pietro (Aaron Taylor-Johnson) into a kickass speedster not unlike his mutant doppelganger in X-Men: Days of Future Past while Wanda (Elizabeth Olsen, Taylor-Johnson's onscreen wife in last year's Godzilla) acquires a potent range of mental and physical powers best summed up as "witch." The twins keep the Avengers busy while Ultron builds an army of robots for them to beat up later, along with machines to pick things up and put them down -- a whole city of things, pulled up by the roots to be flung back to earth in lieu of a convenient asteroid. If you're a comics fan and you recognize the character names you can guess how some things turn out, and the rest of you can probably figure out how using that city as a weapon works out without my spoiling things.
Apart from a ghastly slow-motion money shot of the whole team attacking a Hydra base, there's an admirable matter-of-factness to the first big action scene. Whedon wisely sees no need to give each Avenger a big intro and throws us in the middle of frantic action. Overall the action sets no new standards, and it may be a point against the new film that its best fight scene has almost nothing to do with Ultron. In true Marvel style it's an intra-team throwdown between a Wanda-addled Hulk and an Iron Man in enhanced "Hulkbuster" armor that allows Stark to go toe-to-toe with the Big Guy. It may follow news footage of September 11, 2001, too closely for comfort after the combatants bring down a skyscraper (verified empty of people, of course), but it's thrilling to see Stark really take the fight to Hulk. Comics fans may question the result but the movies have a different pecking order and the outcome is satisfying in context. Meanwhile, our title villain (James Spader in a mo-cap performance) is actually the weakest part of the film. The original comics Ultron, created by writer Roy Thomas and artist John Buscema, was an American Dalek. Mouth locked in a perpetual scream, exclaiming the rodomontado typical of early Marvel, Ultron was a destructive brat who, though canonized as an arch-foe, was long a laughingstock among comics readers. His habit of renumbering himself only served to remind us of how often he'd been beaten. The character as originally conceived requires melodramatic rage but Spader delivers pseudo-intellectual snark in a manner some find all too typical of Whedon. His vocal performance rarely rises above peevishness, as when he responds to another attack by the Hulk with, "For the love of God!" Nearly as bad is the Vision, the android built by Ultron to house his evolving mind but taken over by Stark's old JARVIS operating system. Paul Bettany's performance is no problem, but the character's abrupt introduction and the film's insistence that his goodness and loyalty aren't to be questioned for an instant, in the context of the core team's constant questioning of each other, may make you gag at having him forced down your throat. In comics the Vision was one of the longest-serving Avengers -- he eventually married Wanda -- and he deserved a more dramatic intro than this.
As before, the overqualified core cast -- Downey, Evans, Hemwsorth, Johannson, Renner and Ruffalo -- carries the picture. Their byplay, molded by Whedon in characteristic fashion, can turn a throwaway line like fuddy-duddy Cap chiding Stark for swearing into a gag running the length of the picture. They can have a party (including support heroes from other Marvel films who seem scheduled to be future Avengers) that does not leave you waiting for Ultron to show up. The comics have always been more about the team and its internal issues than it's been about the villains, and with that in mind this film, with the attention-hogging Tom Hiddleston offscreen, feels more like a Marvel comic than the first one did. That doesn't make it a better movie, but that does make it a solid Marvel movie, and Marvel might assure themselves of more solid movies by realizing that with character interaction (fighting included) the main attraction you don't have to threaten the planet every time out. The comics don't work that way, after all, and while I'd concede that a movie has to be a bigger deal than any one monthly issue of the comic book, it shouldn't have to be that much bigger a deal, or else you'll soon run out of ways to potentially destroy the world. The stakes on screen don't necessarily have to reflect the stakes on the financial ledger. Do that too much and the movies will ruin the comics, since the monthly story is going to start looking insignificant by comparison. It'd be a shame if Marvel Comics's spawn, the Marvel Cinematic Universe, became a Frankenstein monster, or an Ultron in his own dreams, that proved the death of its creator.