Sarah is the ex-fiancée of Zack Johnson.
Sarah was supposed to have dinner with Zack, Leonard and Penny at a restaurant, but she couldn't make it because she had an emergency. During dinner, Zack offered Penny a job at his menu company. When Leonard and Penny discussed this, Penny called Zack to tell him she'll take the job, but there was bad news. When Sarah found out that her fiancé was offering a job to his ex-girlfriend, she said it was a stupid idea and she threw a shoe at Zack and left a little bump on his forehead. She was not heard of again, especially since Zack showed up with a wife named Marissa.