5 times Sheldon stole the show with his weird The Big Bang Theory lines (but savage Penny stole it right back from under his nose)

While Sheldon had a smart way to steal the show on The Big Bang Theory with his quirky and often inappropriate one-liners, Penny almost always humbled him.

Their friendship dynamic only grew stronger as the sitcom progressed, but Penny often had the upper hand with her smart comebacks, which Sheldon didn't even understand.

Here are 5 moments from The Big Bang Theory when Sheldon tried to steal the show, but Penny outsmarted him instead.

5 times Penny outsmarted Sheldon in The Big Bang Theory

1) The Laundry night

Penny knew Sheldon was a 'creature of habit,' and thus she defeated him at his own game. Since Sheldon always does his laundry on Saturdays at 8:15 p.m., Penny knew it would not sit right with him if she somehow interrupted his laundry night ritual.

In The Big Bang Theory Season 2 Episode 7, when Sheldon goes to do his laundry at the designated time, he sees that Penny has already occupied all the machines in the room. Seeing through Penny's tricks, Sheldon tries to warn her by saying:

''Woman, you are playing with forces beyond your ken''

To this, Penny puts her hilarious twist and savagely replies:

''Yeah, well your 'ken' can kiss my barbie.''

2) The new Cheesecake Factory policy

While everyone knew Sheldon's peculiar food habits, he was a bit too much for Penny when she was a waitress at the Cheesecake Factory in the initial seasons. In The Big Bang Theory Season 2, when Penny took everybody's orders except Sheldon's, he reminded her of his special order:

''You forgot my barbeque bacon cheese burger. Barbeque sauce, bacon and cheese on the side.''

To this, Penny savagely replies that Sheldon is banished from the Cheescake Factory under a new policy and gets on his nerves:

''No shoes, no shirt, no Sheldon!''

3) The best three-time knock moment on The Big Bang Theory

While this was more of a sweet moment between Penny and Sheldon, it still shows how Penny had gained the upper hand in her friendship with Sheldon throughout the seasons. While initially irritated with Sheldon's three-time knock rule, she started to enjoy it over the seasons, as in this moment from Season 5 Episode 10.

When Sheldon says his best line on the show:

''Penny, Penny, Penny''

She finds it an excellent moment to play with Sheldon, and every time he is about to say Penny, she says:

''Who do we love?'' [followed by Sheldon's 'Penny' three times]

4) When Sheldon crossed the line

While Sheldon and Penny became the best duo on The Big Bang Theory over the years, Sheldon was initially dismissive of Penny as Leonard's girlfriend. In Season 2, when Leonard starts dating Dr. Stephanie, Sheldon says she is the only tolerable girlfriend his friend has ever had (including Penny).

Further, he asks Penny not to let her sexual drive come in between Leonard's relationship and says:

''I'd suggest you suppress your [s*xual drive]''

While Sheldon clearly crossed the line here, Penny savagely replies:

''I could think about you.''

5) Sheldon and Penny's grocery shopping

In Season 1, Penny toned down her sarcasm, but she still had moments where she mocked Sheldon in her fun way. After Sheldon self-invites himself to Penny's grocery shopping, he starts stating random facts about vegetables and fruits, trying to prove how smart he is (and how ignorant Penny is).

While Penny is looking to buy Tomatoes, Sheldon shows off by saying: