Nannies never get the same kind of respect in real life that they usually do in the movies," says Suzanne Hansen, a former nanny herself and the author of the hot new memoir You'll Never Nanny in This Town Again: The True Adventures of a Hollywood Nanny (Crown; $22). "My experience has been that with most families," Hansen says, "if one nanny doesn't work out, you just call up the agency and get a new one. Nannies are as disposable as trashcan liners."

Hansen knows whereof she speaks. For several years, she was the live-in kid wrangler for such high-powered Hollywood couples as Danny DeVito and Rhea Perlman, and Debra Winger and Michael Ovitz. It was Ovitz, the vindictive, one-time superagent, who unwittingly gave You'll Never Nanny in This Town Again its name.

Hansen's book (which made it on to the New York Times bestseller list on Feb. 12) comes smack in the middle of what appears to be a bona fide, pop-culture nanny renaissance. Books like Emma McLaughlin and Nicola Kraus' bestselling novel The Nanny Diaries are doing well, and TV reality shows like Nanny 911 and Supernanny have built impressive audiences. Now, Emma Thompson's mildly perverse film Nanny McPhee seems to have lodged itself in the box office Top 10.

Hansen has made it her business to study all nanny-related art forms, mainly because everyone keeps asking her about them. In the case of Nanny McPhee—adapted by Thompson from the popular Nurse Matilda books and starring herself as a grotesque, firm-handed English nanny with heavenly powers and a devilish sense of humor—Hansen wasn't initially eager to see the movie.

"Based on the trailers," she says, "I thought it was going to be some creepy thing with kids locked in the closet, and I don't really go for that kind of thing. So I was glad that it turned out to be a pretty good movie with a decent message."

"A movie that that just happens to begin with the announcement that a widower's misbehaving children have recently eaten the baby," I remind her.

"Right. I thought that was funny," Hansen replies.

The film, starring Colin Firth as the widower, is fairly typical of nanny movies from Mary Poppins to Sound of Music on down in that it carries the message that the only reason children misbehave—and the only reason they make it a hobby to chase away their nannies—is because they need more time with their parents. In Hansen's professional opinion, that succinct suggestion usually tends to be more or less true.

"You see a lot of that in the wealthy celebrity families," she says, "where the children do tend to be extremely disrespectful because the parents are gone all the time and no one has given them a lot of discipline."

"So you get kids trying to scare off their nannies by putting frogs in their beds?" I ask.

"That happens, absolutely," Hansen says. "Not children who put frogs in their nannies' beds exactly, but children who just won't behave. Either consciously or unconsciously, kids believe that if the nanny goes away, then they'll get their parents back. They meet the new nanny and think, 'If you weren't here, my mom and dad would be.'"

In the movie, when sweet-faced housekeeper Evangeline (Kelly MacDonald) tells the children that she likes them, one of the kids shoots her down, saying, "Yes, but you're a servant, you're paid to like us."

"That really hit me," Hansen says. "The kids know you are paid to be there, so they are very suspect, they doubt that you can really love them and care about them. That part really stung when it happened in the movie, because it's happened to me."

Hansen's favorite thing in the movie was the way the cook (played by Imelda Staunton) kept claiming that the children weren't allowed in her kitchen, and that she had that rule "in writing."

"The cook with the contract was hilarious!" she says. "I nearly wet my pants over that. She was so proud of that contract. She'd probably had so many experiences working for so many families where the children wreaked havoc on her kitchen that she finally got in down on paper. She was so proud of herself, and she should be, speaking as someone who never got a contract on anything. It was so cool of her."

"It still didn't stop her from being tied to the table and pummeled with vegetables," I point out.

"Well, that's true," she laughs. "But then this was a fantasy."

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