The USA. Not all of it -that would be silly- he took on the task of transforming the diets of the children in the (officially) fattest town in America - Huntington, West Virginia, a town where fully half of the population are clinically obese.
No, I've never heard of it either.
From this starting point, he means to transform the American diet from top to bottom, but it won't be easy. At the local radio station where Jamie launches his campaign, they resent his interference on principle. "We don't want to sit around and eat lettuce all day," says the presenter, who appears to be one of those lucky people who makes a living out of being pissed off all the time. Nice work if you can get it.
Jamie's revolution begins at Central City Elementary, where the dinner ladies are serving 450 schoolchildren pizza for breakfast. The kitchen is incredibly well appointed, but the equipment is used exclusively to heat up frozen food.
Hang on a minute, who the hell has pizza for breakfast? And why are the kids having breakfast at school anyway?
If you happen to know the answers to those questions, do let me know.
Anyway, he set up mission control in the kitchen of an elementary school, where the cooks, led by an unpleasant biddy called Alice, looked about as pleased to have him in their midst as they might a Mexican bird-eating spider. As Jamie grew more indignant at the "crap" they were serving the children, Alice and her gang got crosser and more defensive. Irresistible forces meeting immovable objects usually yield good telly, and so it was here, but it was uncomfortable viewing too, not least when our hero, unused to such antagonism, broke down and sobbed and when Jamie's other project in the town, the Edwards family -who feature a 12 year old the size of a Volkswagen- ceremonially buried their deep fat fryer and all made a salad for dinner.
Oliver often seems tremendously cocky, hugely pleased with himself, and yet remains immensely engaging. That's pretty much the image he projects here, too, but here we're seeing a less familiar vulnerable side, which I fully expect will make him even more popular, adding yet more momentum to the Jamie marketing juggernaut.
Nevertheless, it was brave of him to take on the Americans and their addiction to junk food. Whatever happens in Huntington, it's an unwinnable battle. But it will be fascinating to watch him fight it.
"Huntington?, Yeah, bruvva, it's great"