Superhero movies live and die by the quality of the villain, and Ultron might be the coolest, creepiest and most menacing bad guy in the Marvel universe.

The ominous robotic threat is at the heart of "Avengers: Age of Ultron," opening Friday, the latest installment of the ongoing Marvel cinematic universe, the first of two movies out this summer. (Come back in July for Paul Rudd's "Ant-Man.")

"Age of Ultron" has all the things you want out of a summer blockbuster: familiarity, fluid action and comedy. The globe-trotting plot takes the Avengers from threat to threat battling Ultron (motion-captured and voiced by a brilliant James Spader) and his mechanized militia.

The movie starts out in Eastern Europe, where the Strucker (Thomas Kretschmann), a Hydra operative, is experimenting with Loki's scepter -- the big MacGuffin everyone is after here -- to give people powers. The Avengers attack to get the scepter and face off with two of his successes: The Scarlet Witch (Elizabeth Olsen), who has hypnosis and telekinesis powers, and Quicksilver (Aaron Taylor-Johnson), who is super fast.

After the Avengers successfully acquire the scepter, Tony Stark (Robert Downey Jr.) and Bruce Banner (Mark Ruffalo) secretly use the magic gem inside it to create an artificial intelligence as part of a global defense program. But that goes awry with the birth of Ultron, a giant-sized robot who decides the best way to bring peace throughout the world is to kill all humans.

The creation of Ultron eventually leads to the creation of The Vision (Paul Bettany), an ethereal, powerful android that matches up nicely against Ultron. Cue the big fight.

Spader's Ultron is the real marvel of this movie. Not unlike Spader's "Boston Legal" lawyer character Alan Shore, the pensive monster holds court with an entrancing vocal delivery. The performance is amped up with an inhuman, stilted gait. Should the Academy ever be willing to acknowledge or consider a CGI role for an Oscar, Spader's performance is certainly deserving of a Best Supporting Role nomination.

There's a lot going on in the jam-packed 141-minute run time, but writer/director Joss Whedon knows how to tell a story and balances the fisticuffs with some tender and funny moments. All the characters in the overloaded cast get their moments. And some of the best scenes in the film are the quieter ones that take place at a remote country house. And, of course, the ones with giant evil robot.