Actor Jim Parsons accepts the Best Actor in a Comedy Series award for "The Big Bang Theory" at the 4th Annual Critics' Choice Television Awards at the Beverly Hilton in Beverly Hills, California June 19, 2014. REUTERS/Mario Anzuoni
Actor Jim Parsons accepts the Best Actor in a Comedy Series award for "The Big Bang Theory" at the 4th Annual Critics' Choice Television Awards at the Beverly Hilton in Beverly Hills, California June 19, 2014. REUTERS/Mario Anzuoni Reuters/Mario Anzuoni

Sheldon, Raj, Howard and Leonard are at the cafeteria. Raj talks about a new invention. Leonard says that they had a similar idea but they never worked on it. Sheldon tells him that it is because of Penny that he did not pursue that idea. Leonard does not think Penny is the reason why he did not pursue that idea. Sheldon asks him what has been his accomplishment since meeting Penny. According to Howard and Raj, Leonard's accomplishments have been sleeping with Penny, getting her back after she has dumped him, tricking her to get engaged.

Sheldon adds that they all have been distracted since the girls entered their lives. He sees Amy also as a distraction. The four think of planning a science retreat to come up with ideas. Leonard asks Penny if it is okay to cancel their Sunday brunch as the guys are planning a science retreat. Without giving Leonard an answer, Penny asks Amy and Bernadette about going to Vegas for weekend. The two girls say yes and are excited.

Howard is surprised that Raj is joining them for the brainstorming session, as he has a steady girl-friend now. Raj informs the guys that Emily is working that night. Leonard says that they have 48 hours and there are no girls to distract them, "let's change the world." Sheldon adds "thinking caps on." Raj feels that they are in the Facebook movie. Howard has not seen the movie and Sheldon says that they should watch it. Leonard, however, stop them from watching the movie. He flips through an old diary to check their list of old ideas. Howard's ideas include robot girlfriend and robot prostitute. Soon, Leonard closes the diary.

Sheldon says that a lot of inventions have been based on science fiction. Raj points out that the future to back show in "Back to the Future" Part II is just a year away and a lot of things in that movie have not been invented yet. The four guys end up watching the movie. Something does not make sense to Howard and the white board is used. Leonard gives his explanation. Sheldon has a problem with Leonard's usage of tense. Later Sheldon tells Raj that the word wiener comes from Austrian capital Vienna. Leonard stops that talk by saying that they sent the girls away so they could work. Raj says that it is not working.

Meanwhile at Vegas, Penny cannot join the girls for drinks as she has got only two days to study some material for work. Bernadette and Amy return to the room drunk and want Penny to come with them to watch Australian strippers. Penny has to study. Amy runs away to the walk-in closet with Penny's iPad. Penny is sober and has her iPad at the stripping club. Amy and Bernadette are drunk and are acting like Penny.

The guys shift to Leonard's lab. They still do not come up with ideas for invention, as they keep going off topic. They want to confirm something online and end up checking random stuff. When Sheldon suggests that they should adopt behavioural modification to stop themselves from going off topic, they end up watching pigeons playing ping-pong. This leads them to try out medieval torture practice. They put strips of duct tape on their arms and Leonard says that the strip would be yanked off from the arm of the one who goes off-topic. Sheldon immediately goes off-topic and Leonard yanks a duct-tape strip off his arm. Sheldon is not happy and he yanks a strip off Leonard's arm and there is a chain reaction.

Leonard says that negative reinforcement is not working. Sheldon says that the word negative reinforcement is wrong and even Bill Murray made the mistake in the first scene of "Ghostbusters." This talk leads to the four watching the first scene of the movie. Later, they move back to the apartment to watch the complete movie.

And at Vegas, the next morning, Penny goes off to the pool. Amy and Bernadette are unable to get up from the bed. Before leaving the room, Penny draws apart the curtains, letting the sunlight come inside the room. Amy falls when she tries to get up to close the curtains.