Brad Bird’s “Tomorrowland” has so many good ingredients, including a solid performance from George Clooney and some eye popping visual effects. Another good thing is the mystery of it all: Bird doesn’t play his cards too early and keeps us guessing at every turn. But I’ll say this much: George Clooney plays Frank Walker, a grumpy inventor who goes on a mission with a young science nerd (Britt Roberson) to discover the secrets of a place called “Tomorrowland” . When we first meet him, played as a kid by Thomas Robinson, he’s on a visit to the 1964 World’s Fair trying to sell scientist David Nix (Hugh Laurie) a primitive jet pack he devised by himself. I won’t go into spoiler territory. But I will say that truly original science-fiction ideas are few and far between, at least within the realm of Hollywood movies, so “Tomorrowland” scores some points for both its premise and its execution—up to a point. It’s a handsome, eye-filling movie with striking production design by Scott Chambliss and cinematography by Claudio Miranda (who won an Oscar for shooting the beautiful “Life of Pi”). The trouble with “Tomorrowland” is that the closer we get to the story’s conclusion the less interesting it becomes. It remains fairly solid up to the three-quarter mark and measuring once again by Hollywood science-fiction standards, that’s not bad. The movie held me in its grip and, although it sounds superficial, I didn’t mind looking at its beautiful images. But science-fiction, as much as any genre, depends on a great idea at its core, and this one simply isn’t original enough.