Penny informs the gang that she has got a part in some NCI T.V. show. She is playing the role of a customer in a diner who gets to fly with Mark Harman. She is brimming with joy and believes the small role is going to open the doors for bigger opportunities in movies and on television. However, the joy does not last for long, as her part gets edited out.
Penny is depressed and frustrated. Leonard makes an attempt to cheer his girl, but isn't much successful doing that. When asked for an honest opinion, Leonard tells Penny that her chances of becoming a successful actor are slim to none. He tells her that she is talented and beautiful but Los Angeles is full of talented and beautiful actors. Also, Leonard points out that the odds of anyone becoming a successful actor are million to one. Leonard's honesty infuriates Penny more. Later Leonard gives Penny a form for audition of Star Wars movie. He tells her that all the nerds are auditioning. Penny gives-up when Leonard mentions the name of Howard Wolowitz as one of the people auditioning.
Penny, in an inebriated stated, comes to Leonard's apartment. Leonard tells her she has him when Penny complains about not having anything to show after 10 years of being a struggling actor. Penny holds his shoulder and says, "I do have you. Let's get married."
Penny gets down on her knee and properly proposes to Leonard. She asks, "Leonard Hofstadter, will you marry me?"
Seeing no 'Yes' coming from Leonard, Penny is frustrated. Leonard says that he loves her but she is drunk, sad and feeling lost. Penny takes the offer off the table, as she thinks Leonard does not want to get married to her. Penny walks out of Leonard's apartment.
As no one thinks Sheldon is funny, he studies scientific theories to be funny. He thinks that a joke is a "brief, oral narrative, with a climatic humorous twist." He tells Amy that element of surprise is central to being funny. Sheldon also drops his pants to get Amy's reaction. Amy finally finds that funny and as a result, he bores her down with trying to find out usage of which word is funnier.
Sheldon asks Leonard if his relationship with Penny is off when Leonard tells him that he did not reply to Penny's marriage proposal. Leonard does not know that and is sleepless and sad. Sheldon acts all mature and serious, which surprises Leonard. Sheldon says sorry and then later sticks a "Kick Me" note on Leonard's back. Leonard correctly guesses that asks him to remove that.
Raj brings along Stuart to watch Penny's big debut on television. Bernadette thought he would be bringing a cute girl with him. Howard suggests that he should go to mall and talk to regular girls for the sake of practice. Raj and Stuart land at a mall. The two spend the whole time in the mall, without talking to any girl. Stuart points at a girl and Raj rejects that girl because of some reason or another, including she is too classy or she is not hot at all. The idea of talking to a regular girl does not take-off. A mall security guard tells Stuart and Raj that it is time to close the mall. Raj makes a small conversation with the security, asking him about his work. The conversation makes both Raj and Stuart happy.
At the end of the episode, Howard's audition for the new Star War movie is interrupted when Bernadette screams for the toilet paper.