Clocking in at 140 minutes, Avengers: Age of Ultron feels like a speed-reading of a trade paperback, collecting together six issues of a story arc, and leaving one exhausted from the experience.

Joss Whedon is a good writer of lighthearted adventure stories but stains himself when reaching for a dramatic gut-punch, most often resorting to weepy sentimentality that fails to pay off in a movie built around extravagant digital battle sequences. Oddly enough, Whedon’s writing is most effective in the comic-book format, where the reader can decide how long to gaze longingly at an exquisitely drawn action scene before darting through jokes and exposition.

It follows that the most impressive moments in Avengers: Age of Ultron are those where the action is slowed down, allowing the viewer to soak in the complicated scenario of flying bodies and objects moving gracefully through the air. Otherwise, the action sequences are in the usual modern style of frenzied activity that is nearly impossible to comprehend until it stops, revealing writhing or motionless bodies.

What remains is a story that sounds borrowed from T2: Judgment Day (which borrowed from other sources): Artificial intelligence becomes self-aware and decides to destroy mankind to protect the future. Here, the self-aware artificial intelligence is known as Ultron and is voiced magnificently by James Spader, who gives Ultron the kind of weary resignation one might expect in a Shakespearean performance.

Accidentally birthed by Tony Stark (Robert Downey Jr.) — and by “accidentally,” I mean a wince-inducing coincidence of timing that is embarrassing to behold — Ultron decides first to wipe out the Avengers by creating his own army of mighty andoids. Fortunately for the Avengers, he takes his time about it, allowing them to regroup at a secret location after an initial defeat and mope about their lot in life before hurling themselves back into action.

Whedon’s wit provides, well, comic relief from all the melodramatic character meltdowns. While Whedon’s first stab at a superhero team-up movie functioned as a culmination of what came before, in the form of movies focusing on individual characters and their struggles, Avengers: Age of Ultron feels far more perfunctory, more like an engine idling in someone’s driveway waiting for a long-delayed guest.

With two gal pals — Tony Stark’s better half Pepper Potts, and Thor’s romantic partner Jane — left offscreen, Whedon shifts the romantic focus to Black Widow (Scarlett Johansson) and her burgeoning relationship with Bruce Banner (Mark Ruffalo), aka Hulk. It’s portrayed as a dynamic coupling, but no erotic sparks fly between them; it’s closer to the comfortable chemistry expected of longtime married folks. Also, there’s no consideration of the riskier aspects involved; after all, what if something upset Bruce while they were making love and he became the Hulk? A broken bed would be the least of her concerns.

Fitting neatly into the limited expectations I had for the movie, Avenger: Age of Ultron is nothing more and nothing less than a big-budget action movie that takes no risks and delivers no surprises. Help yourself.

The film opens wide throughout North Texas on Friday, May 1.