What this movie needs isn’t criticism, but a stake through the heart. Stop it now or this nerve-numbing killer will rise up again one night on cable TV or at the local video store and siphon off your time, money and wits. No one is safe. MGM, the film’s distributor, is slowly sneaking out its unholy spawn, starting in the boonies and dodging major cities where national reviewers might warn the unsuspecting populace. This report stems from a field trip to the far reaches of Massachusetts. The first reaction, before torpor sets in and audience members acquire the look of glaze-eyed zombies, is disbelief. That can’t be Madonna playing a frumpy ’30s-era missionary. The Madonna of those stylish pop songs, videos and the 1985 film hit Desperately Seeking Susan is a sexy, sassy vamp. The lifeless Barbie doll here cannot walk, talk or say a line without sounding as if she were reciting by rote from a cue card. And that can’t be her real-life husband, Sean Penn, playing a seedy opportunist hired by this missionary to help recover an opium cache. (The mission needs the drugs, lost during the Japanese occupation of China, for medical use.) The Penn of such films as Bad Boys, Fast Times at Ridgemont High and At Close Range is an actor of skill and sensitivity. The Penn here is a clod. Aping the young Clark Gable, in tattered shirt and scruffy beard, Penn succeeds only in looking like a twerpy teen in Daddy’s clothes. The thud, thud, thud heard by the audience are the stars’ attempts at humor, action and romance falling flat. Under the circumstances, those self-satisfied smirks the Penns keep flashing at one another are maddening. Why didn’t Penn, infamous for decking cameramen, zap into action here, where it might have done some good? Jim Goddard, of TV’s Kennedy and Reilly: Ace of Spies miniseries, is listed as director. Again incredulity. No professional could deliberately make actors look this bad. The dialogue, credited to John Kohn and Robert Bentley, seems improvised by students just beginning a class in English-as-a-second-language. When the jokes, which range from racist to bathroom, fail to liven things up, the filmmakers throw in a rickshaw chase or a close-up of exploding bodies. A Shanghai surprise, the script explains, is a slick piece of packaging that contains a bomb. Since the description also applies to this movie, perhaps the MPAA, as a service to viewers, should replace its PG-13 rating for Shanghai Surprise with a new and more helpful classification: HO, for Hands Off.