 Despite initial reports stating guest actress Theresa Russell would be playing a recurring character , the episode marked her only appearance as an adult version of the character . Russell plays Rebecca Kibner , a former test subject and love interest of Walter 's ; a younger version played by actress Tegan Moss is seen in the season premiere " A New Day in the Old Town " . In the DVD audio commentary , the writers explained that when they were looking for an actress to play the character , the casting director April Webster , acting on Jeff Pinkner 's instructions , called Kibner both " a blessing and a curse , " because the writers wanted to explore the burden of what it meant to be special . One writer explained Kibner and Walter 's past relationship had not been a long term affair , but instead more of a " little fling " . The episode also marked the first appearance of Canadian actor Ryan McDonald as recurring character Brandon Fayette , a Massive Dynamic scientist . According to the episode 's writers , the character is based on a man who works at the production company Bad Robot . 
