Clark must save Pete from being devoured by Jody (guest star Amy Adams), ravenous from hunger. Meanwhile, Lex funds a study on the green meteor fragments, bringing him one step closer to the truth about Clark.

Who is Jody? A friend of Pete, Chloe, Clark and Lana. Jody is a good student, but teased and unhappy because of her obesity. She goes on a crash diet, consuming only veggies grown with kryptonite. Losing weight overnight, a thinner Jody asks Pete to be her date to Lana's birthday party. Jody's diet helps her lose pounds quickly, but gives her a ravenous appetite. In an uncontrollable eating binge while driving, Jody hits a deer on a rainy road. Animal survival instincts kick in, and Jody eats the body fat of the freshly killed carcass.

What's up with Lana? Aunt Nell is planning a fancy birthday party for Lana at Lex's mansion. Whitney can't make the party because he must attend a meeting at the university about a football scholarship. Clark takes the opportunity to ask Lana if he can escort her to the party. She accepts.

What's up with Clark? Clark is trying to think up a special birthday gift for Lana. Chloe says she'll help if he goes to animal control with her to snoop around about the accident and the death of the deer. Later, hungry Jody flirts with school jerk Dustin, who had previously teased her cruelly about her weight. Jody attacks Dustin. Clark hears the noise and uses his x-ray vision to see two people struggling. He finds an emaciated Dustin, begging for help. Dustin ends up in the hospital, due to loss of body fat.

What's up with Lex? Although Lex is otherwise healthy, his doctor tells him he has an elevated white blood cell count, common in Smallville, perhaps due to local theories of environmental damage caused by LuthorCorp. Concerned about his health and his company, Lex starts investigating. He asks Clark about his memories of the meteor shower. Lex feels his future was defined by that day, making him stronger. After talking to Chloe about her meteor theories tracing back to Smallville weirdness, Lex visits Dr. Hamilton about kryptonite, eventually funding his research with a $100,000 grant.

What's up with Chloe? Chloe figures out what's going on with Jody, just before Lana's party.

What's up with Pete? Jody is super-model thin wearing a red dress as Pete comes to the house to pick her up for the party. Jody gets one of her hunger attacks, and runs inside to avoid Pete. He follows, and she tells him to leave. They struggle, and Pete is knocked out when his head hits the floor. Just before Jody attacks, Clark arrives. Jody runs outside to the greenhouse. Clark follows, but is powerless because of the kryptonite. Feeling she's a freak, Jody breaks the gas line, causing an explosion. Back to consciousness, Pete comes out and Clark tells him they have to get Jody to the hospital.

How it ends: Lana is stood up by Clark at her birthday party. Clark shows up afterward at Lana's house to give her his gift. Sitting in his truck, they watch Bugs Bunny cartoons projected on the side of the barn, sweetly reminiscent of Lana's happy drive-in movie memory with her parents.