|Actor|| Sean Owen Roberts|
|Episode(s)|| 7.03 The Girl Next Door|
7.05 Shut Up, Dr. Phil
7.06 Slash Fiction
Chet is a Leviathan who has taken the form of a credit card company employee.
When Sam makes purchases on a credit card with the name Lemmy Kilmister, an alert pops up at the credit card company where Chet works. He immediately calls Edgar and alerts him that Sam or Dean have made a purchase in a shop in Montana. Edgar tells him to follow up. At the shop, Chet checks the security footage and calls Edgar to confirm that it was Sam. He plans to pursue the Winchester, but first eats the store employee, after dousing him in molten cheese.
Chet gets instructions by phone as to the Winchester's location and says he's about a day and a half's drive from Prosperity, Indiana. When he finds Sam and Dean, Dean shoots him, but his body simply pushes the bullet out. As Chet is about to attack, Don Stark enters and knocks him about with some sort of electrical power, which he says will disable him for a day or two. He advises the Winchesters to put the creature in a a bottomless hole. Sam and Dean bind Chet with chains, and put him in the back of the Impala.
Bound in the basement of Rufus' cabin, Chet reveals that Edgar is still alive. He also tells Sam and Dean that he found them using an algorithm to track their known aliases.which the Leviathans learned from when they were inside Castiel. When they ask Chet why he's telling them anything, he tells them to watch the news, where they find their dopplegangers on the rampage.
Bobby continues to try and find something that will harm or kill Chet. Bobby cuts off his head with a machete, but it later reattaches itself to his body.
Bobby gets too close to Chet, and Chet transforms into Bobby. The Leviathan takes a look at Bobby's thoughts and then taunts him. Then something from the ceiling drips on Chet's arm and starts eating away at his flesh. Chet screams in pain, and Bobby rushes upstairs to see what is leaking through the floor. He finds Sheriff Jody Mills cleaning the floor with a solution containing Borax (Sodium Borate).
Bobby later gives Chet's head to Jody and asks her to toss it in the river while he intends to inter Chet's body in cement.