The Penny Theory That Changes Everything On The Big Bang Theory

If you really think about it, we barely know anything about The Big Bang Theory's Penny (Kaley Cuoco) who, until she marries Leonard (Johnny Galecki) in season 9, doesn't even have a real last name. She's beautiful and blonde, but that doesn't mean her supposed acting career is going anywhere. She can somehow afford to live in an apartment building expensive enough that a couple of working scientists can afford to live in it in spite of her waitress' salary. All the while, her character seems to have nothing at all in common with Leonard and his friends. Yet she still spends almost all of her time hanging out with them, eating Chinese food, and listening to them nerd out about subjects she doesn't seem to grasp.

It speaks to a crisis in the very foundation of the show's premise that these inconsistencies are never probed, let alone explained. Look too hard at the character Penny, and you'll see all the cracks that should have brought the entire structure of the series crumbling down around the sheer improbability of this one woman's choices and traits. Fortunately, there's a fan theory that provides an explanation for all of these apparent plot holes, and its implications are pretty darn wild to comprehend. 

Dare, if you will, to read on and find out what fans have speculated about Penny's true motives for getting close to Leonard and Sheldon (Jim Parsons).

The Spy Who Loved Leonard

According to this fan theory, first posited by Reddit user /u/numbertheory and picked up by Screen Rant, it's quite possible that Penny is secretly a spy. That's right — move over The Americans, because Chuck Lorre's got an entirely different story to tell about a deep cover agent living among her unwitting marks. 

The theory ties into the notion that the federal government has been spying on Sheldon and Leonard ever since Leonard broke up with Joyce Kim (Ally Maki), a woman who was revealed to be a North Korean spy in the episode "The Staircase Implementation." An upset Leonard causes an explosion that takes out the building's elevators, which may not interest local authorities for very long but — coupled with the Kim incident — very well could have drawn the attention of the federal government. Aware of Leonard and Sheldon's knowledge of a rocket fuel project, they simply sent Penny in to monitor both men, according to the theory.

We know. It sounds absurd, but it actually ties up all of the lingering confusion about Penny's lifestyle. Think about it: Penny, without even an identifiable last name, has been sent into the men's lives to observe their antics. This explains why she spends so much time with two guys who don't share her interests, why she lacks any friends of her own, how she can afford an apartment without a roommate, and why there's a lack of traction in her so-called acting career. All obvious violations of Occam's razor aside, sometimes it's the explanation that actually explains everything that's worthy of consideration — unlike the real-life Big Bang Theory, ironically enough. You can think of it as a Unified Theory of Penny. 

Penny could tell you her last name, but then she would have to kill you

If you're still having trouble wrapping your head around the possibility that Penny is the cunning spy next door, then consider this: Despite Penny's lack of multiple PhDs, The Big Bang Theory makes it clear that she's not an idiot — far from it, in fact. Without the slow reveal of Penny's intelligence over the course of her long character arc, would her relationship with the objectively brilliant Leonard even work? 

Maybe — just maybe — she plays it all "babe in the woods" whenever the boys descend into science-talk just to keep their guard down. Maybe she feigns a total lack of understand, to lure this apartment full of useful idiots into a false sense of security. If they knew right from the get-go that Penny understood even a fraction of what they were saying, maybe they would have been more guarded with the details of their work. Penny's abject — some would say performative — ignorance provides them with just the level of comfort they need to spill each and every classified bean. All the while, if this theory is to be believed at least, Penny could be carefully recording any and all information the boys might reveal that could be of interest to federal intelligence.

Now go back and watch the entire series from the beginning with this new understanding. It's a totally different show.