Execution is everything, and the producers of ABC’s “Wife Swap” prove it tomorrow night by adding wit and emotion to a compelling reality premise. It’s a rare combination, considering how well it always works. The reality shows I’ve kept up with (“American Idol,” “Queer Eye,” and the first five episodes of “The Apprentice”) all toy with emotion for dramatic effect. But in going directly to the heart of the American family, “Wife Swap” creates a narrative that redeems the marriages it disrupts. By the end of the first, wonderfully touching episode of this season’s best reality show, you’ll believe a man can cry.

You’re not going to like Jodi Spolansky much. But that’s okay, because you’re not supposed to. She’s a new kind of bad girl for reality TV: the Bad Mom. Jodi’s a mother of boys who has four full-time nannies to tend to them while she pursues the good life. She makes repeated reference to “me time,” and as a Manhattan rich girl she devotes her days to chauffeur-driven jaunts into the shopping district to drop thousands of dollars a day. She gets her muscles worked over by Radu, the celebrity trainer, and eats out every single night. She confesses right away that she hasn’t cooked in years. Sure, she’s selfish and annoying – but you’ll find something about Jodi endearing. Maybe it’s her willingness to openly embrace her selfishness. If it’s an act for the cameras, then good for Jodi. She’s an actress now.

Jodi’s trading places for two weeks with 45-year-old Lynn Bradley, a housewife from rural New Jersey who gets up before dawn every morning to chop wood before driving the local school bus. She’s got a bunch of kids, too. On top of everything else, Lynn does all the cooking and cleaning. Her husband, Brad, is a humble fellow with a handlebar mustache. Very little has come along to change Brad’s life in quite some time; you can see the boredom in his face, which is what makes his transformation so entertaining. At first he hates the arrival of Jodi, whose profound annoyance with all responsibility sends the family into immediate chaos. The chaos escapes the Spolansky home, of course; the nannies are there, remember? Lynn gets a makeover, goes out to dinner with friends, and sleeps in through breakfast.

The structure of “Wife Swap” adds a clever second act to the story, by allowing the women to abandon the existing rules of their new home and establish new ones. The wife creates her own model family, using the existing husband and children as actors in her improvisational sketch. It’s funny, and not in the forced way common to most reality shows. There’s none of the faux-idiot character that Paris Hilton plays on “The Simple Life.” The Spolanskys and the Bradleys are allowed to show the full extent of their intelligence, and no one does much to embarrass the human race. In fact, they’re oddly compatible; they leave you with the feeling you get when you click together two peculiarly shaped puzzle pieces. If the chemistry works this well every week on “Wife Swap,” this could become addictive.

Unlike “The Apprentice,” a serial soap opera, “Wife Swap” presents a new self-contained episode each week. We don’t have any more room in our life for shows we have to watch all the time, or miss out on key plot points. Your life won’t change by seeing “Wife Swap,” but it’s worth checking out for a week or two. The first episode resolves in a touching reunion that almost seems believable; when Brad says, “I’ll never get back the 10 days of my life that I lost not living with my wife,” he means it. Maybe Brad’s marriage needed the tiny jolt of reality that came with the arrival of Jodi Spolansky in his life. That could be the message of “Wife Swap,” if you’re willing to believe it has one – that sometimes we don’t know what we have until it’s gone.

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Shelley Ross, the new executive producer of ABC’s “PrimeTime Live,” has demonstrated just how unhip she is adding a weekly musical-comedy segment to the show, “That Was the Week That Was,” taken directly from the 1960s BBC series produced and hosted by David Frost. It’s an arcane and unsuccessful nod to what once seemed daring and sharp – “That Was the Week That Was” being the name of a jazzy tune interspersed with gags about current events. With the appealing Kristy Glass on vocals accompanied by a piano, the newsmagazine has successfully re-created the feel of a smoky 1960s cocktail lounge, probably of the sort where Mike Nichols and Elaine May performed in their early days as nightclub comics.

I wanted the idea to work, but must report that it doesn’t. The segment pales by comparison with more sophisticated and funny topical comedy available elsewhere on TV, most notably on Comedy Central’s “The Daily Show” with Jon Stewart. Beyond that, its anachronistic feel jars the sensibility of the show it self, which otherwise seems committed to jazzy editing and sizzling production values. What would possess Ms. Ross to throw a 42-year-old comedy gambit into the mix? It seems odd, coming from the producer who helped Diane Sawyer become what she is today: the best morning personality on television. (That includes the now insufferably bubbly Katie Couric, who grows more annoying by the day.) Ms. Ross owes it to Ms. Sawyer to junk “That Was the Week That Was,” and find something truly funny to replace it – something with a little more bite than “forget about the issues, it’s all about the tissues.” With humor sketches, as both of them know very well, it’s all about the jokes.