Morgan Spurlock subjects himself to a diet based only on McDonald's fast food three times a day for thirty days without exercising to try to prove why so many Americans are fat or obese. He submits himself to a complete check-up by three doctors, comparing his weight along the way, resulting in a scary conclusion.

Muckraking filmmaker Morgan Spurlock reignites his battle with the food industry — this time from behind the register — as he opens his own fast food restaurant.