When Langley Falls implements a ban on trans fats, Stan finds himself legally separated from his favorite foods. He sets a poor example for the rest of the family when he blatantly disregards the law by crossing county lines and using Steve as a trans-fatty food mule to satisfy his own gluttonous desires.

Bart gets a perfect score on a practice test for a national achievement test, which not only rattles Lisa, but it means Bart gets to attend a special party instead of having to take the actual test. Meanwhile, Homer must avoid injuring himself for an entire afternoon after failing to pay his insurance.