Dexter "Dex" McCallum was the husband of Louise McCallum and the great uncle of Lana Lang. His best friend, Deputy Billy Tate framed him for the murder of his wife.

Forty years later, in intensive care, Dex wrote a letter to Lana and asked her to visit him, so that he could tell her his version of the story. He loved his wife, and he wanted someone in her family to know that he did not kill her. He suspected that a drifter killed Louise. Lana thought that his sketch of the drifter looked a lot like Clark Kent, so she decided to investigate. Clark and Chloe Sullivan got in on it, too, and they discovered that the drifter was Clark's father, Jor-El. He loved Louise, too, but he did not kill her. William Tate hired Lachlan Luthor to kill the drifter, but he accidentally killed Louise instead. Clark convinced Tate to confess, and Dex was released from prison.