Is This the Secret Formula Behind Grey's Anatomy's 300-Episode Run?

When I realized that today marks Grey's Anatomy's 300th episode, I did a literal, cartoon-style jaw drop. But why was I so surprised? That show has been on since my middle school days and has gone through more cast members than I have Tinder swipes.

I started watching Grey's in season 3, specifically with the two-part ferry boat accident episode, you know [spoiler alert if you've been living under a rock through 300 episodes:], the one where Meredith tries to drown herself. For the next four years, I was hooked. Something about the medical drama combined with the social drama kept me coming back until that weird musical episode. (Callie wasn't even really singing and honestly, the Scrubs musical ep was WAY better.) I didn't quite make it to Christina's final episode—or Mark's, or Lexie's or Derek's—mostly due to my love of the original characters. Once most of them were gone, so was I.

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But plenty of people continued to binge the show, for THREE HUNDRED episodes. New characters arrived that audiences came to love, like Owen, April, Arizona, and Jackson. (Are any of them still on the show? Unclear.) And Grey's isn't the only beloved show to have an incredible run of 300 episodes. Law and Order: SVU, NCIS, and The Simpsons have all joined the 300 club. How do you explain their longevity?

What NCIS, Law and Order, E.R., and Grey's Anatomy all offer is the drama-within-a-drama format, which gives viewers the satisfaction of closure in every single episode—but also leaves them with a cliffhanger.

The closed drama occurs in the form of the crime or medical mystery plot, and there is no shortage of twisted stories to serve up there. In every episode, we're introduced to a new catastrophe. We experience the adrenaline spike, but we know our hard-working doctors or detectives will solve the case.

But while you experience the relief, the sense of fulfillment, that comes along with solving the mystery or saving the day, the social drama, the real juicy plot that keeps us coming back for more, unfolds at a glacial pace. We're so distracted by the excitement of this week's crime/medical storyline that every date, every rejection, every tiff between friends—which make up the series' larger arc—can take a full episode or more. As a result, we become attached to the characters, but we don't tire of their personal drama. (Plus when all the docs are easy on the eyes, tuning in every week to watch them work their magic rarely disappoints.)

Cartoons like The Simpsons which, it seems, will be airing until well after the nuclear apocalypse, are more of a mystery to me. Family Guy and South Park have yet to hit 300 episodes—but they're both so close, with 293 and 283 episodes respectively and counting. Likely, animated longevity can be explained by bang-for-your-buck production. Thanks to smart writers and actors who have the ability to voice more than one character, there really is no end in sight for a LCD laughs, adult-catered cartoon.

So pick yourself a good medical/crime drama or a for-adults animated show. They're in it for the long haul.