Supernatural: 10 Best Characters Who Only Appeared In One Episode

An old flame of Dean Winchester's, Cassie Robinson calls him after her father’s death. Her father had reported that a black truck had been following him around shortly before his death and that of his friend.

The authorities brush off these demises as mere accidents, but Cassie is convinced that there is a supernatural element at play. Her editor is killed at the same spot that claimed her father soon after her call with the Winchesters. She tries getting the mayor to close that section of the road but he refuses.

The Winchesters go to Cape Girardeau, Missouri, and start investigating the suspicious deaths. In between, Dean and Cassie reminisce about old times, dissect their relationship, have a mini-fight, apologize to each other, and have make-up sex.

After the Winchesters solve the case and dispose of a vengeful spirit, Dean tries to renew things. Cassie doesn't think there's much hope for them but Dean is adamant. He insists that we will return promising, “Cassie, I’ll see you. I will.” He never sees her again.