[s3e15] The Large Hadron Collision Here

is the 15th episode of the third season of The Big Bang Theory , which originally aired on February 8, 2010. In this Valentine's Day-themed episode, Leonard is invited to visit the Large Hadron Collider in Switzerland and must choose between taking his girlfriend, Penny, or his roommate, Sheldon. Plot Summary

During his campaign, Sheldon hugs Penny after she briefly agrees to talk to Leonard. However, Penny catches the flu just before the trip. Leonard tries to take Sheldon instead, only to find that Sheldon has also caught the flu from the hug. [S3E15] The Large Hadron Collision

"The Big Bang Theory" The Large Hadron Collision (TV ... - IMDb is the 15th episode of the third season