Disney’s history of imagination is unparalleled, but the studio’s shaky track record of sci-fi is paved with the likes of The Black Hole, The Computer Wore Tennis Shoes and Tron Legacy. So the squandered opportunity for redemption is mighty in Brad Bird’s Tomorrowland (C-), an ambitious film that is full of ideas but misses the mark on executing most of them. The vapid protagonist played by Britt Robertson speaks mainly in cliches, and when she partners with George Clooney in what is basically an extended cameo, he doesn’t add much either to the proceedings aside from faux Han Solo gruffness. There’s lots of overreach about saving mankind from its own destiny, but Bird doesn’t do a good job outlining the plot to properly take audiences along for the ride. What’s left are a few lovely nostalgia scenes, some half-sketched visions of the future, some awkward robots (TV’s Small Wonder was more believable) and an underdeveloped sense of majesty. The film, overstuffed with good intention, is mostly a bloated bore.