Grade: C-

Harrison Ford saves the day again in “Firewall,” a movie that’s like “Air Force One” without the presidency or the plane. In a way you can’t blame the actor for going back to the straight-arrow-guy-in-difficult-circumstances shtick that’s served him so well over the years, especially since when he’s tried something really different, audiences have often rejected the result. At the same time, one has to admit that in this case the formula feels awfully tired, the plausibility quotient is ludicrously low, and Ford himself seems a bit too long in the tooth to engage in such heroics (particularly in the big fight scene he wheezes through at the close).

Of course, Ford’s haggard, rumpled mien is supposed to be a function of his character Jack Stanfield, a Seattle bank security executive who’s already stressed over a pending merger with a much larger outfit–his boss (Alan Arkin) is irritated with his obstructionist attitude, and he’s bumping heads with the officious expert from the bigger bank (Robert Patrick) on site to handle the details of the consolidation. But that’s nothing compared to the pressure he feels when one of those ruthless villains so common in thrillers like this–a smoothly malevolent fellow calling himself Bill Cox (Paul Bettany)–takes charge of the Stanfield home, imprisoning Jack’s loving family (wife Beth, teen daughter Sarah and cute-as-a-button tyke Andy–played by Virginia Madsen, Carly Schroeder and Jimmy Bennett, respectively–as well as the family dog) under the none-too-kindly control of his goons and threatening them with severe bodily harm unless Jack helps to transfer a hundred million bucks from the bank’s holdings to his Cayman Island account.

What follows is a scenario that increasingly strains one’s ability to suspend disbelief. Jack is fitted with an array of high-tech microphones and video cameras that track his every move while his family cower in fear back at the old oceanside homestead. Attempts to escape fail. Cox’s plan proves impracticable, forcing Jack to come up with an ad-hoc scheme to outwit his own security system and get him the money he wants, especially after the nefarious Cox–a pity he doesn’t have a moustache to twirl–goes so far as to use little Andy’s allergic reaction to peanuts to force his hand (the cad!) Incidental figures–Jack’s colleague Harry (Robert Forster), who may or may not be in league with Cox, and his mousy secretary Janet (Mary Lynn Rajskub) are drawn into the mix as Stanfield tries to turn the tables on his foes and save his own compromised skin as well as his wife and kids. The whole business gets more and more convoluted, involving car chases, police, fisticuffs, an attempted frame, a canine location collar, one crook who goes softie, another dispatched for ineptitude, a big explosion and that grotesque final confrontation; but though explanations are provided in passing for everything that happens, the elements hang together by a very slender thread, and the picture crosses the line from the unlikely to the ridiculous far too frequently. (The script may be attributed to a fellow named Forte, but that doesn’t mean it’s strong in any department.) The periodic attempts at humor are especially weak, and all the episodes concerning the Stanfield children in jeopardy (not only little Andy’s susceptibility to the wrong foods but the ever-present possibility that teary-eyed Sarah might be assaulted) are extremely unpleasant.

Recognizing the fragility of the narrative, director Richard Loncraine tries to obscure the weaknesses by speeding things along, but the tension never really builds, and by the protracted finale the energy seems to have seeped out of the movie. Ford doesn’t help much with a perfunctory performance that trades on his familiar mannerisms rather than creating much of a character, and though Bettany goes through the nasty paces demanded of him, his is a stock part that hardly tests his thespian mettle. Madsen, Schroeder and Bennett feign fright decently enough, Rajskub wiggles her nose in an effort to make us find her irresistible, Patrick carries off the officiousness shtick well enough, and veterans Arkin and Forster walk through their roles without breaking a sweat. But none of them add any distinction to the mix. Nor is the picture very attractive visually; Marco Pontecorvo’s camerawork is pedestrian, as is Brian Morris’ production design and Helen Jarvis’ art direction. Even Alexandre Desplat, one of the most interesting film composers working today, contributes a score that’s far below his best–not just conventionally pulsating but intrusive.

But that’s typical of a picture in which everyone seems to be going through the motions without much conviction. And their half-hearted attitude, unfortunately, is transmitted all too successfully to the audience. “Firewall” is no blast.