Kurt plays the role of Penny’s former boyfriend. The two lived together after Penny moved from Nebraska to California.
Kurt, unlike the guys, isn’t very bright, but he’s a tall, muscular, and formidable guy. Kurt and Leonard naturally have some beef, and it takes Penny some time to get over Kurt, although she finds him to be a jerk.
Margo Harshman as Alex Jensen – Then
Alex is pursuing her Ph.D. in Caltech Physics and works as Sheldon’s assistant. Sheldon often gives her tasks that are unrelated to their research.
Alex wants Leonard and asks him on a date, but Leonard says no because of his loyalty to Penny.
Margo Harshman as Alex Jensen – Now
Margo’s acting career didn’t start in TBBT, rather back when she was a kid in "Even Stevens," playing the role of Tawny Dean, the best friend of was Shia LaBeouf’s character, Louis Stevens.
Margo has played several smaller parts since TBBT, like Alison Kidman in "Bones" and Delilah Fielding in "NCIS."
Brian Patrick Wade as Kurt – Now
Brian has played several roles in TV and movies before his role in TBBT. He acted as Mitch Lyons in "The Guardian" and Fatneck in "Bring It On Again."
He also played small parts in "Two and a Half Men," "Arrested Development," "Teen Wolf," and "Agents of Shield." At the moment, he is taking a break from acting and working as a personal trainer.
Valerie Azlynn as Alicia – Then
Alicia is Leonard, Penny, and Sheldon’s former neighbor who lives in the apartment above them. She first meets Leonard and Sheldon in the lobby, where Sheldon bombards her with annoying questions. Annoyed, Alicia nonetheless answers every question, and Sheldon accepts her.
Leonard, Howard, and Raj swoon over her, doing her many favors. Penny is annoyed that Alicia is taking advantage of the boys and jealous. Penny tells the boys that Alicia is using them. The two get into a quarrel after Penny confronts Alicia about this, resulting in Penny’s black eye and the boys stopping to do things for Alicia.