Picture 5 / 6
![Picture 5 / 6](/images/uploads/1/rs_279c527d31ebbc09b67.jpg)
The Monopolar Expedition
Season 2, Episode 23 - Aired May 11, 2009
When Sheldon is offered the opportunity to research at the North Pole, he invites the guys along with him. The impending expedition forces Penny & Leonard to reconsider their feelings for each other.