Since Penny moved out of 4B, she has not just left the apartment empty but Leonard heartbroken. He never really got over the fact that she had left him, even one year later. But as he walks up the stairs to his home this one Thursday, he spots moving boxes in the hallway infront of his door. Curious on who he and Sheldon will get as a new neighbor, he walks towards the open door. At first, he can't see anyone in the apartment, but as he wants to turn around and walk away, he hears a female voice coming from the kitchen of 4B.