On tonight’s Big Bang Theory, the guys discuss the weird relationship between Stuart and Mrs. Wolowitz while having lunch at the university. Howard tries to shake it off, pretending it isn’t weird that they are wearing matching pajamas.
The girls on the other hand, are discussing their prom nights at Penny's apartment. Amy shares that she was on the clean up crew, so her date was a mop. They even shared a slow dance together. Penny and Bernadette agree that their proms weren’t that special or memorable. They decide that they should throw a prom redo.
The guys and Penny sit around and discuss the prom event. Leonard notices that Penny seems to be blowing it off since she isn’t out dress shopping with the other girls.
Bernadette finds that everyone responds “yes” to the prom. She points out that Stuart is coming with a date. They both think this is Mrs. Wolowitz. Bernadette thinks it is perfectly fine, bringing up to Howard that he took her to his prom. He tries to explain that she was just a chaperone, but Bernadette says she saw a picture of them dancing together.
Howard calls Stuart and tells him that he doesn’t want him bringing his mom. Stuart assures Howard that he isn’t, he has another date.
Sheldon shows up at Penny’s apartment with an idea of how they can enjoy the prom. His idea, which he thinks is wonderful, is that they should pretend to be aliens. He believes that pretending to be an alien is a good coping mechanism. Penny thinks his idea is weird, so she goes off on a tangent. She asks Sheldon if he, as an alien, will be participating in the post prom mating ritual with Amy. Sheldon is unaware that prom night can come with certain expectations. Sheldon says that if it is truly part of prom, then he is open to it because “aliens have urges too.”
Leonard helps Sheldon fix his bow-tie. He mentions that he will not be an alien since nobody else wants to. He grabs a flask so he can take part in the ritual of spiking the punch—with pomegranate juice. Leonard mentions that a lot of people lose their virginity on prom night. Sheldon gets nervous, now that both him and Penny have brought it up.
Howard, Bernadette, Raj and Emily go to pick up Stuart only to find out that his date is Howard’s cousin Jeanie. She is the cousin Howard previously had sex with. He tries defending himself saying she is his second cousin and they were fifteen. When she gets in the limo, naturally, things get awkward.
Leonard and Sheldon go to pick up the girls. The girls come out and Sheldon gets nervous. He goes back to his apartment saying he can’t do this.
Amy goes to see Sheldon, who believes he is having a panic attack. He explains that there is a great deal of pressure for them to “make whoopee.” Amy tells him she is going to go to prom alone. Sheldon leaves his room and stops Amy. He tells her that she looks pretty and that is what made him nervous. She lets him know that they don’t have to spend the night together. He asks her if she was hoping that they would. She tells him she is always hoping, but she really just wants to dance with him. Amy gets up the courage and tells Sheldon that she needs to tell him something, but he doesn’t have to say it back. Before Amy can get it out, Sheldon says “I love you too,” much to her surprise. Amy is so shocked, she starts to have her own panic attack.
Penny and Leonard are the first and only two at the rooftop prom so far. The two romantically dance together. When the rest of the group arrives, they take cheesy prom pictures. That is when Howard gets a call from Mrs. Wolowitz who seems jealous that he is there with Jeanie. Stuart assures her that they are just friends, before running off to see her.