While not in the same disastrous class as Ed Wood’s Plan 9 from Outer Space, Steven Spielberg’s War of the Worlds clearly fails to live up to expectations. The moment two youngsters appear more frightening than attacking aliens, you can’t help suspecting there’ll be additional moviemaking trouble ahead. And you’re right. Excessive flashes of light, jerky camera movements, illogical behavior by major characters and a sappy ending -- all emerge to sabotage this disappointing film update of H. G. Wells’s classic sci-fi novel.

None of the problems here seem to be star Tom Cruise’s fault. He delivers a strong performance as a divorced father trying to save his son and daughter from a terrifying alien onslaught. Still, the script requires him to do some things that boggle your mind -- such as taking drastic measures to silence a very creepy Tim Robbins (mustn’t let the aliens hear us) right after telling his daughter to sing. Or searching through a box of condiments for food instead of looking in a refrigerator. Nit-picky? Maybe, but in a movie filled with giant tripods zapping everyone and everything they can see, is it too much to expect the humans to act like real people?

Now, back to those scary youngsters. As played by Dakota Fanning and Justin Chatwin, Cruise’s two kids come across as prime candidates for “Brat Camp.” Fanning, so terrific in all her previous films, frowns or screams during most of her scenes (and there are a lot of them) in War of the Worlds. Chatwin just glares and insults his dad. Of course, these two siblings would rather not be with their irresponsible father for the week-end. They prefer living with their pregnant mother and stepfather -- which doesn’t excuse their obnoxious behavior. Cruise’s character may not be likeable either -- for example, he gives his daughter a peanut butter sandwich, oblivious of the fact that she’s been allergic to peanuts since birth -- but at least he’s making an attempt to get along with his kids. And, by the way, why can’t Fanning and Chatwin fix their own sandwiches, for gosh sakes. She’s eleven and he’s a teenager. Arrrrgh!

“I wanted Ray (Cruise’s character) to become like a lot of people because he has to represent all of us,” Spielberg explains. “He and his family are representing our own fears, our own facilities to survive, our own resourcefulness.” 

Sorry, Mr. Spielberg, that’s precisely where your War of the Worlds falters. Throw in all the horrifying aliens, terrified crowds, blood-drenched countrysides, crumbling buildings, amazing set pieces and eye-popping special effects you want -- but if the human characters leave us scratching our heads in disbelief, we don’t feel represented at all.

(Released by Paramount Pictures and DreamWorks; rated “PG-13” for frightening sequences of sci-fi violence and disturbing images.)