The episode opens with Sheldon breaking some bad news to Leonard: a team of Swedish scientists are trying to scoop their superfluid vortex experiment, which would help prove the physics theory they formulated together last season. Leonard’s bummed by the news, seeing as they can’t conduct their own experiment for a month due to a shortage on liquid helium. The only person with access to liquid helium is Kripke, who plans on using it for his own experiment. While Kripke has some to spare, he refuses to give Leonard and Sheldon any because he’s feeling particularly petty.
After Leonard and Sheldon explain their dilemma to Howard and Raj, Howard offers up an alternative solution. He knows a guy who can get them the liquid helium, as long as they don’t ask too many questions. That, of course, leads to Leonard and Sheldon peppering Howard with questions about this guy, his helium source, and his occupation.
Meanwhile, Bernadette tells Penny that Stuart actually went on a date, thanks to the help of a new dating app (which sounds an awful lot like Tinder). Stuart’s met a grand total of two women thanks to the app, and also mentions that he’s yet to give a single woman a “thumbs down”, because he’s just that desperate.
Leonard gets in touch with Howard’s “helium guy”, who offers to meet them that night. Sheldon is a bit squirrelly on obtaining the liquid helium illegally, in part because he’d be buying the helium at night (which is something he just doesn’t do). Leonard insists that they wouldn’t be breaking any serious rules, just bending them a bit. Ultimately, Leonard convinces Sheldon with a made up Einstein quote and they agree to meet the guy that evening.
Bernadette and Penny decide to use Stuart’s (not) Tinder app to get Amy back in the dating game, over Amy’s mild protests. However, Bernadette and Penny seem a lot more interested in playing with the app themselves, rather than actually let Amy pick out her own dates. Howard and Raj join in on the fun and soon everyone is gathered around Amy’s phone deciding on whether to say yes to a white dude in dreadlocks.
Leonard and Sheldon meet up with the black market helium dealer in a parking garage. Sheldon introduces himself with a fake name (Skippy) and quickly takes charge of the negotiations, demanding that the helium dealer hand over the helium before they hand over the cash. Soon, the conversation quickly turns to whether Sheldon and the helium dealer are in a stalemate, a Mexican standoff or an impasse. After Sheldon starts explaining the nuances of a Mexican standoff, he accidentally threatens the dealer, thus creating a real Mexican standoff. Leonard defuses the situation by explaining why they need the liquid helium. As he pulls the helium out of the van, the helium dealer says he expected higher ethical standards from the Swedes and then discreetly offers to permanently “take care of” the Swedes, which Sheldon totally misunderstands.
Back at the Wolowitz’s house, Penny and the others have put Amy’s dating app on the television, so everyone can look at Amy’s potential suitors. Amy points out that they’re being a bit mean to these poor guys, so when Stuart’s profile pops up, Raj suggests he leave the room so his feelings don’t get hurt.
Leonard and Sheldon wheel the liquid helium (which is dressed as Sheldon’s Uncle Harvey to avoid suspicion) into their laboratory. As Leonard prepares to set up the experiment, Sheldon sees a partially torn off sticker, stating that the helium’s original owner had a name that began with the letter U. Sheldon immediately presumes the helium was stolen from a government organization. Leonard asks if they’re really going to let the Swedish team beat them because they’re afraid of breaking a few rules, before the show cuts to Leonard and Sheldon hurriedly wheeling the helium out of the building.
Meanwhile, the rest of the gang play a drinking game with the dating app, with participants taking one sip for every shirtless guy they see, two sips for every dude posing with his pet, and chugging their beer whenever a dude is both shirtless AND posing with their pet. However, the revelry is interrupted when Amy gets a text message from the mysterious “Dave”, who says that he had a great time with Amy the previous night and would love to go out on another date. Amy sheepishly explains that she’s started dating, but that she didn’t want to tell anyone because it’s all new and weird.
Leonard sets up another rendezvous to return the illegal container of helium. The helium dealer graciously agrees to take back the helium, but refuses to give them their money back and then charges them a restocking fee for his troubles. When they return to the lab, Sheldon muses that the Swedes might beat them, but at least they won’t get “gang-noogied” in prison (a reference to Ernest Goes to Jail). Kripke suddenly comes in and offers to give them the helium, but demands that his name gets put on their paper in return. Faced with the possibility of getting extorted by Kripke, Sheldon and Leonard see only one solution: they hit up the helium dealer a third time and buy the liquid helium for real this time.
The episode ends with Leonard looking up the definition of a Mexican standoff (Sheldon was wrong) as he, Sheldon and the helium dealer sit down to watch Ernest Goes to Jail back at Leonard and Sheldon’s apartment.