Of course they are beautifully crafted–gleaming, high-tech artifacts, designed, photographed, edited and special-effected to within a millimeter of technical perfection. And director Robert Zemeckis and his co-writer Bob Gale have kept the good-natured, artificially innocent quality that the Spielberg operation has practically patented. But, hey, kids, the real smarts have gone out of BTTF. In the second one (released only six months ago), Marty and Doc found themselves in 2015, with their precious Hill Valley now a technoburb where ads have become zooming holograms, skateboards are hoverboards and tiny pizzas expand instantly to family size in the hydrator. In BTTF III Marty and Doc go into reverse, time-vrooming to Hill Valley 1885, a dusty cow town inhabited by all the cliches of Western movies.

It’s a little late to be spoofing Westerns, and most of the high-noonery in BTTF III falls flat. When Marty shows off his pistol skill at a target range, he’s asked where he [earned to shoos. “7-Eleven,” is the grace-C gag reply. The movie’s pivotal gimmick is the race to rejigger events so that Doc’s scheduled demise doesn’t happen. This pits Marty against his perennial adversary Biff (Thomas F. Wilson), here a gunslinging forebear named Buford (Mad Dog) Tannen. The sight gag here (grade C-plus) is that Buford is a tower of filth who’s constantly falling afoul of cuspidors and manure piles.

As usual with BTTF, double roles abound. Fox also plays Seamus McFly, Marty’s great-great-grandfather. The split-screen images are again dazzlingly perfect, but Seamus is nothing but a flimsy brogue and flimsier red whiskers. The delightful Lea Thompson has little to do as Marty’s mom and Seamus’s wife. BTTF III’s chief twist is Doc Brown’s first romance, with schoolmarm Clara Clayton (Mary Steenburgen). This, too, is a waste of Steenburgen, whose big speech declares her love for Doc and the works of Jules Verne. The only really charming element is Christopher Lloyd’s love-struck Doc. Passion seems to add more frizz to his hair, more pop to his eyes, more rasp to his voice. Is this the last BTTF? Well, the customized De Lorean time machine is now totaled. But suppose there’s $150 million in the till this summer?? Lee Iacocca would be all too eager to donate a new car to Doc.