Chris Evans and Chris Hemsworth in Avengers: Age of Ultron.

When Avengers: Age of Ultron wrapped, I realized a terrible thing for a fanboy like me: I had just watched almost 2 1/2 hours of stuff that did almost nothing for me. It was a big blur, intermittently interrupted by half-interesting moments.

In other words: It was boring.

You can’t accuse director Joss Whedon of “second verse, same as the first” with Avengers: Age of Ultron. He and his team definitely went for something different with this sequel to one of the greatest blockbusters ever made. Perhaps it would’ve been OK to retain more of the good humor, campiness and non-cluttered thrills that made The Avengers such a gas.

Ultron is flat. Nothing of any real consequence happens; there are just a bunch of scenes teasing future Marvel movies, and some action sequences that lack clarity. With the exception of an interesting smackdown between Iron Man and the Hulk, the action sequences feel repetitive.

The “Ultron” of the movie’s title is a series of robots with an artificial-intelligence program initiated by Tony Stark (Robert Downey Jr.). Stark, thinking he can create a security force that will save the world, gets a little ahead of himself, forgoes the approval of his fellow Avengers—with the exception of Bruce Banner (Mark Ruffalo)—and starts the program, only to discover that A.I. can sometimes mean Absolute Insanity. The program goes AWOL and produces the anti-human Ultron.

Voiced by James Spader, Ultron is a one-note villain that lacks personality, unlike Tom Hiddleston’s Loki and other recent comic-book villains. He’s not a formidable bad guy, in part because he’s just a CGI creation voiced by an actor. All of the great Marvel and D.C. villains are usually a little more human, while Ultron comes off as a third-rate Transformers Decepticon. Yes, Spader has a menacing voice, but he’s no James Earl Jones.

On the other hand, the Vision—a good-guy offshoot of the same program that produces Ultron, more or less—is far more interesting. Played by Paul Bettany, the Vision is a welcome addition to the roster. Bettany’s likeness is actually used in the Vision, and he looks cool.

Also new are Scarlet Witch (Elizabeth Olsen) and Quicksilver (Aaron Taylor-Johnson). Scarlet Witch does the mind-control thing, which Whedon illustrates with a visual that looks like mist surrounding her victim’s head. This reminded me of Uma Thurman’s Poison Ivy and her red-mist, mind-controlling pheromones in Joel Schumacher’s Batman and Robin. When it comes to comic book movies, it is never a good thing when something reminds you of Batman and Robin.

Quicksilver is potentially fun, but Johnson’s incarnation is not as interesting as that of Evan Peters, who played the part in last year’s X-Men: Days of Future Past.

The film plays with the notion of Black Widow (Scarlett Johansson) and the Hulk having an affair. We get a couple of scenes with Black Widow managing to get the Hulk to calm down, and a little bit of Ruffalo and Johansson sort-of flirting, but the subplot doesn’t go anywhere. While the original Avengers was a terrific showcase for the Hulk, the latest mostly loses the big green guy in the shuffle. Also, Hawkeye (Jeremy Renner) now has a wife, in a failed effort to raise his character above least-interesting Avenger.

If you are an Avengers fan, you’ll have to see Age of Ultron, because it sets up a series of other films, and you might find yourself lost when watching future movies like Captain America: Civil War, Thor: Ragnarok or Black Widow: She Will Never Have Her Own Movie … What Gives?

As for Whedon, perhaps he was the wrong man for this gig. The sequel goes for a darker tonal shift—a sort of Empire Strikes Back for the Avengers. The result is one of the year’s most crushing cinematic letdowns.

Avengers: Age of Ultron is now playing at theaters across the valley.