Trama

Priya forces Leonard to choose between a relationship with her or a friendship with Penny. A magic trick by Howard has Sheldon fooled.

Priya and Leonard's relationship has gotten to a serious stage where Leonard is wearing the clothes that she picks out for him and is trying to wear contact lenses on her suggestion, even though he can't see with them on. As his serious girlfriend, Priya asks him for a big favor: to stop being friends with Penny. She feels uncomfortable having one of his ex-girlfriends be such a big part of his life. So later, when Priya asks him if he's "talked" to Penny, he doesn't tell the complete truth. How long can Leonard get away with this little white lie before he really has to make a decision between Priya and Penny, especially as Priya is thinking about relocating to southern California for good? Meanwhile, Howard performs a card trick which confounds his friends. Sheldon states that he doesn't care about the trick, but it's obvious that not knowing how the trick is done is killing him.—Huggo

Leonard and Priya are in bed together at Leonard's place. They discuss the racism implied in Leonard's attempt in trying out positions from the Kama Sutra and, shortly after, Priya urges him to get contact lenses as she claims he has beautiful eyes.

Later, at the cafeteria, Howard offers to show Raj a magic trick, but Sheldon intervenes and tells him he shouldn't be wasting his time with such trivial matters. Howard performs the trick anyway and impresses both Raj and Sheldon. Although Sheldon mocks the trick, he is still keen to unravel it. Leonard comes in with his new contact lenses which are clearly incompatible with him, and he crashes into several people and furniture.

Back at apartment 4A, Howard impresses Penny with his magic trick as Sheldon watches carefully, apparently still stumped by the card trick. Leonard comes back from shopping for "more grown-up" clothes with Priya and they head for his room. Priya voices her feelings about Leonard hanging out with Penny all the time and asks him to terminate their relationship, and he reluctantly agrees. Meanwhile, Howard continually impresses his friends with the magic trick, and Penny appears to have successfully figured out the magic trick, which further crushes Sheldon's ego.

Leonard and Penny bump into each other in the laundry room, where Penny "saves" Leonard's new silk shirt that he was about to ruin by throwing it into the washing machine. She goes on to compliment Leonard's choice in Priya as a real winner. Penny gathers her laundry and looks at Leonard for a moment before saying goodbye, but Leonard stops her and nervously tries to hint that he would like to see her less without saying it directly. His obscure method of "cutting their ties" confuses Penny, and she leaves the room thinking no differently of their friendship. Later, when Priya questions him about whether or not he spoke to Penny about this issue yet, he hastily confirms that he has, hoping that the issue is now settled.

Meanwhile, Sheldon has grown increasingly obsessive with understanding Howard's magic trick, and has even gone as far as hacking into the Oak Ridge National Laboratory's Cray supercomputer to analyze shuffling patterns and looks into procuring Uranium-235 off of Craigslist after wondering if Howard used a radioactive tracer.

Later that evening, Priya and Leonard are having dinner at the Tandoori Palace and Priya reveals that her company has offered her a job in Los Angeles. Leonard is thrilled at this news, but as the couple hold hands they're interrupted by a tapping noise and look up to see Penny smiling and waving at them through the window. She then enters the restaurant and makes a scene, mocking Leonard's clothes and appearance before picking food off his plate and drinking out of his glass. These actions anger Priya, who deduces that Leonard never fulfilled his promise to cut his ties with Penny.

At the cafeteria, Sheldon claims he has solved and improved Howard's magic trick. Howard and Raj are interested to see his version of the trick, but soon see that he has bar-coded all the cards and used a bar-code reader to identify it. Howard criticizes Sheldon's execution was pathetic, and Sheldon is once again annoyed, because he assumed they weren't smart enough to figure it out. Howard shows the trick again, but this time it is revealed to the audience that there is no trick, as Raj (and Penny) has been playing along with Howard's wild guesses as a mean joke on Sheldon, knowing that he would go nuts trying to figure it out.

Later, Leonard finally musters up the courage to tell the truth to Penny, and it quickly dawns on her that there are complications in their friendship due to Leonard's current relationship with Priya, and she agrees to keep a distance. She kisses him and tells him goodbye. Leonard goes after her, but runs into the door frame because of his contact lenses.

Sheldon is depressed that he is unable to solve the magic trick. The Department of Homeland Security busted him for hacking into the Cray supercomputer and trying to buy Uranium-235 over the internet. (Rather than arresting him, the DHS let his mother deal with him, which Sheldon claims is a far worse punishment.) Howard offers to show it again. However, this time Sheldon requests Howard try it on him, and Howard reluctantly agrees. Sheldon isn't "gullible" like Raj is, and with his finely-tuned senses, he will spot Howard's trick as soon as Howard screws up. With all of his focus on Howard, Sheldon doesn't notice Raj signaling to Howard that Sheldon's card is the two of hearts. Furiously, Sheldon storms out of the cafeteria as Raj and Howard dissolve into laughter.

Title reference: Howard's faux prestidigitation magic card trick.