Leonard and Penny say "I Do" as they finally tie the knot

Los Angeles: After eight seasons of anticipation, on-off couple Penny and Leonard, played by Kaley Cuoco-Sweeting and Johnny Galecki, are finally man and wife on "The Big Bang Theory" after they exchanged wedding vows during a Las Vegas ceremony.

The pair headed to the entertainment capital of the world to tie the knot in the season nine premiere of the hit sit-com.

But things were not all rosy for the couple as it got complicated when Leonard confessed that he had kissed another girl, which almost jeopardised the wedding.

Eventually things worked out for the fan-favourite couple and they got hitched.

However, their gang of friends - Sheldon, Howard, Raj, Bernadette and Amy played by Jim Parsons, Simon Helberg, Kunal Nayyar, Melissa Rauch and Mayim Bialik respectively - were back in Pasadena and even missed the Skype session when Leonard and Penny said their vows.

The marriage doesn't mean that the volatile couple's troubles are over. Though Penny had assured Leonard that she was over his brief cheating scandal, when the time came on their wedding night, she couldn't stop picturing her new husband with the other woman.

Leonard tried to make her feel better and assured her of how guilty he felt. However, he only ended up making it worse after accidentally revealing that she's one of his co-workers whom he sees on a daily basis.

The honeymoon was cut way short. The not-so-happy couple returned home and went to their separate apartments, leaving viewers to wonder if this will end up being the shortest marriage in TV history.