Just call Never Again ''My Big Fat Geek Relationship.'' How do we know that Christopher (Jeffrey Tambor), a sad-sack exterminator in New York City who dumps any woman the moment she falls for him, is really a deep and caring human being? Because he moonlights as a jazz musician ''in the Village,'' tickling the ivories to crowds of adoring white people. How do we know that he and Grace (Jill Clayburgh), a divorcée plunged into the blues after her daughter leaves for college, are ideally matched misfits? Because these two 54-year-old lonely hearts meet at...a seedy gay disco! The gruesome, sub-sitcom contrivances just pile up from there in Eric Schaeffer's howler of a romantic comedy, which presents itself as a valentine to Clayburgh even as it keeps dreaming up fresh ways to humiliate her.
Grace commiserates with her two best friends in scenes coy enough to make the First Wives Club scurry for cover; she visits a sex shop and parades around her apartment wearing a leather mask and strap-on; she throws a teary public tantrum in which she declares, in effect, ''I am Unmarried Woman, hear me roar!'' Clayburgh and Tambor are charming performers; neither of them deserves Eric Schaeffer.