Joss Whedon's 'Avengers: Age of Ultron,' with Mark Ruffalo, takes a Frankenstein angle

The words "gods" and "monsters" show up in proximity more than once in "Avengers: Age of Ultron," the Marvel Comics superhero movie opening Friday, echoing a scientist's famous toast in "Bride of Frankenstein": "To a new world of gods and monsters!"

Coincidence? No. Writer-director Joss Whedon knows his genre antecedents, and James Whale's 1935 classic is, like "Age of Ultron," about artificial intelligence and artificial life.

"We happen to be living in a time when just about anything you can imagine, someone can bring into being," says Mark Ruffalo, who plays scientist Bruce Banner and his monstrous alter ego, the Hulk. "That makes us feel very powerful and probably godlike, but it also opens up a whole other plane of monsters."

Is he talking about the movie or the real world? "I think both, now," he says. "I was talking about real life, but that's also what the movie is talking about, in a more extreme way."

"Age of Ultron," the latest in a novelistic succession of Marvel movies, follows Tony Stark (aka Iron Man), Steve Rogers (Captain America), the Norse god Thor, superspy Natasha Romanoff, preternatural archer Clint Barton and the Hulk as they retrieve the powerful scepter wielded by Thor's brother, Loki, in "The Avengers" (2012). Thor will deliver it to his interdimensional realm of Asgard for safekeeping. But first, Stark suggests studying it for a couple of days.

In Frankensteinian fashion, this leads to the creation of Ultron -- an artificial intelligence who thinks "peace in our time" means engineering a global-extinction event to give new, hopefully improved life a chance to evolve. And where A.I. is concerned, both in film and in real life, "There's this uncharted territory we're moving into," believes two-time Oscar nominee Ruffalo. "And maybe we see technology as the answer to everything, but at the same time it could be the end of everything."

Not that making the movie was all existential doom and gloom, he assures. The day they shot the scene in which "we're all sitting there playing with [Thor's] hammer, trying to pull the hammer up off the table -- that was just one of those magical days where we were all together and really just kind of hanging out," Ruffalo reminisces. "We were improvising a lot and it was just delightful."

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Plus, later in that scene, Ruffalo's Banner finds himself lying atop Scarlett Johansson's Romanoff. "Honestly," Ruffalo says with a laugh, "that was funny because she was pregnant and we had to figure out how to do that scene without hurting the dear, dear, dear new baby inside of her."

As any fan will attest, Banner's closest relationship is with fellow scientist Stark, played by Robert Downey Jr. "I think that's informed a lot by Downey and our relationship and who he is in my life." Ruffalo says. "There's an ease there because of where we've come from and where we find ourselves today.

"Plus," he adds, "I just think it's fun to see those dudes do science -- seeing those bros bro down over science."