Messing with a classic movie can be dangerous business, which is probably one of the reasons why Guess Who achieves only a modicum of success. This mildly amusing film updates Guess Who’s Coming to Dinner? by reversing the story’s racial representation. Ashton Kutcher stars as the unwelcome boyfriend originally played by Sidney Poitier, and Bernie Mac takes on Spencer Tracy’s disappointed father role. Obviously going more for laughs than the original, Guess Who relies too heavily on the comic talents of Kutcher and Mac, rather than on a meaty script or cinematic artistry.

However, while poking fun at the problems of interracial romance, the movie manages to remind viewers that discrimination and stereotypes are still alive and well in the new millennium. One scene involving a number of racial jokes disgusted me, but I have to admit I’ve heard -- and, sadly, chuckled at -- some of them before.

Kutcher (Just Married) and perky Zoe Saldana (The Terminal) portray lovers who intend to announce their engagement during the weekend Saldana’s parents (Mac and Judith Scott) host a party celebrating renewal of their wedding vows. Saldana hasn’t told her family about her new boyfriend’s race, and Kutcher can’t help being frightened by the prospect of meeting her dad, whose photos make him look immensely intimidating. Complicating matters, Kutcher quits his job without telling Saldana -- and this is a big deal, especially since Saldana’s father wants her to date only men with good jobs.           

When Kutcher and Mac (Bad Santa) meet, any romance in the movie takes a back seat to the relationship between the two men. Ebony and ivory clash as these very different guys try to outdo each other in a silly go-cart race, spur-of-the-moment sports activities and tango dancing(!) -- all of which give rise to just a few humorous moments during their extensive screen time together.

The movie’s funniest sequence belongs to Kutcher alone. It involves a series of frantic “make-up” calls to Saldana after she finds out about his jobless situation.  Pleading, cajoling, demanding, wooing -- you name it -- he tries everything he can think of to win her back. Kutcher’s acting here may be the best he’s ever done. It certainly proves he doesn’t need pratfalls or slapstick to make us laugh.       

Although Mac failed to impress me during most of Guess Who, he redeems himself somewhat in the final “wedding vows” scene. That man can sing (or lypsynch?), and he really knows the right moves! Unfortunately, it’s a case of too little, too late.

I don’t want to end this review on such a harsh note, so let me say Guess Who is not a total waste of time. Without being too preachy, it’s a painless way to learn lessons about the dangers of racial prejudice as well as the importance of honesty in a romantic relationship. And finally, for some strange reason, I’m compelled to mention again how much I enjoyed Ashton Kutcher’s memorable telephone antics.

(Released by Columbia Pictures and rated “PG-13” for sex-related humor.)