A well-oiled machine of visuals, and yet a wobbling rattletrap of storytelling, the sci-fi fantasy “Tomorrowland” is an unwieldy clunker driven into the ditch at full speed. Injured in the accident were George Clooney as a boy inventor turned adult cynic, Britt Robertson as a spunky teen optimist, Hugh Laurie as a generic villain, and many viewers.

Like “Pirates of the Caribbean,” “Tomorrowland” is a Walt Disney Pictures promotional tie-in to an exhibit at its resorts. There the similarity ends. The “Pirates” saga did delightful, spoofy world-building around its yo-ho-ho theme. “Tomorrowland,” for all its pictorial gloss, goes back to the future badly.

It imagines an era ahead when scientists have invented progressive, exciting technologies for Earth’s salvation. Or have they? The few able to venture from the present into this world soon learn that promised things are seldom as good as they seem, much like the trailer for “Tomorrowland.”

Framed as a time-traveling adventure, it is a mystery film keeping the audience as ill-informed as the characters. It races torpedo-style from scene to set piece regardless of whether they advance the convoluted story, wobble astray or even make sense. Rarely do we see a Disney family film where ray guns repeatedly zap humans to ashes, the heroine is a repeat car thief, the bad guy has his legs painfully crushed for a minute before his skull is crushed, and the main man is madly romantic for a girl who could pass for his granddaughter.

Even worse, the incoherent ideas are unconnected. It’s as if screenwriter Damon Lindelof (who scripted those dreadful houses of cards “Cowboys and Aliens,” “Prometheus” and TV’s “Lost”) is trying to hit the young target audience with a Gatling gun.

Confusion begins at the starting gate, with Clooney scowling as the cantankerous on-screen narrator. He is Frank Walker, a grumpy home-brew scientist arguing with an unseen female speaker about how to tell their enigmatic story. Even before it begins, we are lost in Wonderland. How did the mismatched pair team up? Whom are they addressing, and how and why? These questions, and many more, the overlong film answers only after much audience watch-gazing.

– Ghost Protocol”) handles well. He knows how to deliver big-budget spectacle. Does it advance the story? No. Aiming his flight pack high, Frank wildly misses the mark, much like the film.

Frank’s character disappears into a decades-long sulk and we shift to a parallel plot line. Millennial idealist Casey Newton (Robertson) is a troublemaker to the high school teachers and police opposing her independent-minded schemes. Plucky but rarely law-abiding, she tackles the world’s problems with sheer willpower, her motorbike and robot drones.

She and Frank team up when, five minutes into her first visit, hostile androids raid his house. Leaping into his rocket-powered escape bathtub, they zoom toward Earth’s destiny like Dorothy and the Wizard ballooning to Oz.

Clooney gives his insufferable role a dash of rich ham flavor, adding the correct tone of amusing excess to each gripe. Robertson lends her miscreant character a degree of nerve and curiosity, implying that she’s smarter than the script illustrates. Hugh Laurie makes the antagonist a patronizing jerk just like the one he played in “House,” while Raffey Cassidy gives her vigilant preadolescent a nice balance of girlish emotion and kung fu acrobatics.

In a blink-and-you-miss-it scene as a sci-fi shop’s geeky owner, Keegan-Michael Key — in a zany wig and muffin-top fat suit — climbs to the top rank of walk-on comedy players. If only the right cast could improve bad writing through performance alone.