Running from 1955 to 1961, The Life and Legend of Wyatt Earp was among the very first series that presented a continuing storyline—and that used the recap sequence. A few voice-over sentences usually sufficed to summarize the events of the previous Tuesday evening, because the show really only had one plot line, one life and legend. Its first season was a sort of mini-series: six episodes with a major story arc—unusual on television in those days, although then again everything was. These were the pioneer days, and everyone was experimenting.

As far as fictional storytelling went, television executives quickly found they wanted shows that could be scheduled to run in any order, and multiple times. “Reruns were big business,” says Tim Brooks, the TV historian and former network executive. “It’s very difficult to program things with a week-to-week schedule.” So they discarded serialized storylines in favor of standalone 30- or 60-minute episodes, to let viewers tune in at their leisure. Networks could replay old episodes without worrying about narrative context, and maximize their financial gain. The standalone format, which accordingly had no use for the recap sequence, reigned for decades, organizing comedies and procedurals and dramas alike. It’s worth mentioning, though, that some of the most popular shows of the day did devise other kinds of entrees into the situations of their comedy, like certain theme songs now indissoluble from memory (Gilligan's Island, Beverly Hillbillies, I'm looking at you). Each episode was a fresh start, a welcome wave to viewers veteran and probationary.

Storytelling—and in turn, recap sequences—didn’t much evolve until the late 1970s and early 1980s with the rise of “quality” primetime soaps and police dramas like Dynasty and Knot’s Landing, which embraced storylines that arced over whole seasons. A 30-minute, snappy resolution wasn't the first priority, though nor was novelistic complexity; these shows were a kind of stepping point. “For the first time, it was important to know what happened before,” TV historian Gary Edgerton says. “And it was important to follow along.” Edgerton says that the knitted architecture of these shows challenged viewers at first, but a new form of recapping—the splice-and-dice from previous episodes that's now so intimately familiar—became integral in ferrying the viewer along to the following week. It was also helpful for viewers who still treated television as a medium of convenience—if you'd missed last week’s episode, the recap was there.

In the ‘90s, critical and popular hits like Twin Peaks, The X-Files, and Buffy the Vampire Slayer dramatically upped the stakes of what television plots could look like. A sophisticated narrative with sophisticated characters became a broad expectation. And increasingly, the recap evolved from summarizing what happened “previously on” and became a new kind of narrative form unto itself, essential to the mechanics of the show it represented.