Even those whose nerd blood runs lukewarm should acknowledge the skill with which The Avengers did its thing, throwing together multiple franchises into a jumbo combo pack that somehow didn’t feel like a letdown. Age of Ultron is, it must be said, a clunkier affair than its predecessor, shoehorning too many new characters into a narrative that devotes more time to setting up future conflicts than to resolving the ones in the constantly exploding now. And yet, while you’re watching it, none of these deficits really seem to matter all that much. Warts and all, this is one of the all-too-rare preordained blockbusters that doesn’t take the audience’s enjoyment for granted.

Opening with a confidently show-offy battle scene, director Joss Whedon’s script finds Iron Man, Black Widow, Hulk, and the rest putting aside their ideological bickering to square off against the rogue AI Ultron (James Spader, who delightfully refuses to sound even the slightest bit robotic). Things go boom, lasers go kapow, Captain America 3 is up next. Whedon, who has announced that he’s bowing out after this installment, makes the most of having too full of a plate, expanding the action scenes while also ensuring that the quippy wealth is much better distributed among the characters this time around. (Jeremy Renner’s Hawkeye gets the best lines, which even he seems pleasantly surprised about.)

Two hours and change is a long time to mainline anything, really, and Age of Ultron definitely loses some of its juice by the third act, especially when it starts laying the groundwork for all of the Marvel movies down the road. Even at its most cosmically overstuffed, however, the fun everyone seems to be having up there remains infectious. Yes, comic-book movies are crowding out everything else, are the eventual heat death of cinema, and so forth. But, man, there’s just so much neat stuff here. Boom. Kapow. recommended