The Big Bang Theory fans showed their love for the show with their reactions to this season 1 moment featuring Penny (Kaley Cuoco) and Leonard (Johnny Galecki).

Penny has a strange relationship with her family in The Big Bang Theory, and one mystery doesn't help matters.

The Big Bang Theory is one of the funniest sitcoms in recent memory, and these episodes are among its very best.

10 Big Bang Theory Episodes That Will Make Someone Into a Fan After running for 12 seasons, the show is still a top pick for fans, and some episodes show why.