Big Bang Theory Quote
Leonard: Actually, I couldn't get too mad at him about Joyce Kim.
Penny: Why not?
Leonard: Well, I was doing some government research at the time, you know, military rocket fuel. It was kind of secret.
Penny: What does that have to do with Joyce Kim?
Leonard: As it turns out, she was a North Korean spy. Luckily, Sheldon drove her out before I revealed anything important.
Quote from S03E22 - The Staircase Implementation