Carl had always looked back on his days with Justine with much happiness. All that changed when Justine came to Bay City in 1995. Completely insane, Justine kidnapped Rachel and, being her exact double, replaced her. She took over Rachel's life completely, including seducing Carl, who had no idea a switch had taken place. When Carl noticed old scars on her wrists he realized that she was Justine and not Rachel. Carl was forced to maintain the charade for fear that Rachel would be killed. He loathed every minute of it and could barely restrain himself from killing her. When he was reunited with Rachel, he swore vengeance on Justine.
In December Justine attempted to kill Rachel, but Carl intervened and stabbed Justine to death with a letter opener.
Carl made it a habit of bedding his more attractive female partners-in-crime, and Blair was no exception.