In 1987, Jon Hein and his roommates at the University of Michigan were drinking beer and had Nick at Nite playing in the background. They started talking about classic TV shows when someone asked, “What was the precise moment you knew it was downhill for your favorite show?” One said it was when Vicki came on board “The Love Boat.” Another thought it was when the Great Gazoo appeared on “The Flintstones.” Sean Connolly offered, “That’s easy: It was when Fonzie jumped the shark.” As Hein later recounted, there was silence in the room: “No explanation necessary, the phrase said it all.”

Thus was born an expression that would quickly make its way into the pop culture mainstream, defined by Hein as “a moment. A defining moment when you know from now on … it’s all downhill … it will never be the same.” If I had been in the room, however, I would have broken that silence of self-assuredness, for I wrote that now infamous episode of “Happy Days.”

And more than three decades later, I still don’t believe that the series “jumped the shark” when Fonzie jumped the shark.

Little did the show’s writers and producers know as we gathered in a conference room at Paramount Studios that spring day in 1977 that we would be creating a little piece of history. “Happy Days” was finishing the 1976-77 season as the most popular series on television, an accomplishment we were all proud of. That year had begun with a highly rated three-part story in which Fonzie ( Henry Winkler) rekindled the flame of a former love, Pinky Tuscadero. Because of this success, ABC and Paramount wanted us to open the next season, our fifth, with another three-part story.

After discussing different scenarios, we decided to take the “Happy Days” gang to Hollywood, with Fonzie invited for a screen test. One of the plot lines would be Fonzie clashing with “The California Kid,” a cocky local beach boy. Since Henry water skied in real life, it was suggested the characters race and then, as a tiebreaker, have to jump a shark in a netted area in the ocean.

Now, whose idea was it for Fonzie to jump the shark? Amazingly, I can’t remember — which is frustrating, as I can usually watch a “Happy Days” episode from any season, hear a joke and recall who wrote it. My friend Brian Levant, then a talented new member of the writing staff, believes that Garry Marshall, the show’s co-creator and executive producer, and Bob Brunner, the show runner at the time, made the suggestion. But what I definitely remember is that no one protested vehemently; not one of us said, “Fonzie, jump a shark? Are you out of your mind?”

After the stories for the three opening episodes were blocked out, it was time to see who would write them. Often the writer who came up with the story would write the teleplay, while other times the script assignments were given out by the show runner. Bob gave me the final part to write.

There were no objections from the cast, the studio or the network concerning “Hollywood 3,” as it came to be titled. It aired Sept. 20, 1977, and was a huge hit, ranking No. 3 for the week with a 50-plus share (unheard of today) and an audience of more than 30 million viewers.

And that was that until Hein and his roommates appeared a decade later. Not long after their initial bull session, Hein launched https://www.jumptheshark.com, listing about 200 television shows and inviting visitors to suggest the moment they knew a show was on the decline. Incredibly, the three words took off like wildfire and over the years the phrase has been used in television shows, video games and countless newspapers, magazines and blogs — applied to practically anything: sports, music, celebrities, politics. It even found its way into the Oxford English Dictionary as British journalists pondered whether Tony Blair had jumped the shark. I saw a post on examiner.com a few weeks ago suggesting President Obama was about to do the same thing by appearing on “The View.”

Which brings us to the question: Was the “Hollywood 3" episode of “Happy Days” deserving of its fate?

No, it wasn’t. All successful shows eventually start to decline, but this was not “Happy Days’” time. Consider: It was the 91st episode and the fifth season. If this was really the beginning of a downward spiral, why did the show stay on the air for six more seasons and shoot an additional 164 episodes? Why did we rank among the Top 25 in five of those six seasons?

That’s why, when I first heard the phrase and found out what it meant, I was incredulous. Then my incredulity turned into amazement. I started thinking about the thousands of television shows that had been on the air since the medium began. And out of all of those, the “Happy Days” episode in which Fonzie jumps over a shark is the one to be singled out? This made no sense.

Interestingly enough, nowhere in any discussions or articles on the subject of jump the shark did I ever find my name associated with it. So, really, the only people who knew I wrote the episode were those on the show and my friends and family. But I knew. I have to admit, there was a time I was embarrassed. I was Hester Prynne reincarnated, walking around with a scarlet “S” on the front of my shirt, facing accusing glances and stifled snickering. But this feeling passed quickly, and I likened the popularity to a new fad, where someone jumps on the proverbial bandwagon and soon everyone is doing it, for no rhyme or reason, like the riding the mechanical bull craze. It was ludicrous. All I could do was laugh.

Fortunately, my career didn’t jump the shark after “jump the shark.” When “Happy Days” ended, I went directly to the ABC Paramount hit show “Webster” and, after that, wrote and produced, among others, “It’s Your Move,” “He’s the Mayor, “The New Leave It to Beaver” and “Family Matters.” In 1987, Brian Levant and I created the action comedy “My Secret Identity,” which won an International Emmy.

Now that so much time has passed, it’s clear that “jump the shark” is no mere fad. It has become a part of the American lexicon. I often hear or read the phrase and run into people who know it. Some of them aren’t even aware of the origin. It is unfathomable to me that the shark still has its bite.

But so does our show. The day after I started writing this article, my sister Jan was meeting our friend Vicki at a movie screening. Jan mentioned I had written the episode of “Happy Days” where Fonzie jumped the shark and was working on a piece about it for the Los Angeles Times. A young man in his 20s at the reception table overheard and looked at her in disbelief. “Your brother wrote the jump the shark episode?” he said. “Awesome!”

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