During my recent bout of illness I watched about forty hours of Buffy the Vampire Slayer on DVD. I ordinarily watch very little TV (I don't own one) so seeing a concentrated chunk from a single series made me super-conscious of some of the recurring patterns in the show. Series television depends upon recurring patterns for practical reasons, but this has serious artistic consequences for the medium.
Efforts to control production costs necessarily create recurring themes in a show's visual style. The most obvious and important example is the tendency to use the same sets repeatedly, either to represent a location frequented by the characters or to create “new” sets by redressing old ones in new ways. Handled artfully, this can be a real strength, creating a vivid world where the characters live. The bridge of the Enterprise is as much a character on Star Trek as Spock or Captain Picard. Or think of the Stedmans' house on thirtysomething, the endlessly re-dressed cemetary on Buffy, or the garage in Taxi. On ER, M*A*S*H, and The West Wing, the setting is the title character! The recurrance of sets, costumes, and props can also put a television show into an almost pure world of characters and dialogue: I don't think we ever left the two-room office on Barney Miller, giving the show a simplicity that contributed to its distinctive rhythm.
Recurring patterns emerge also from the way that the storytelling in a series interacts with the viewer's time: a show has both a very short and a very long chunk of the viewer's attention. On the level of an individual episode, you have 22 or 45 minutes of screen time, which compels a lot of storytelling efficiency. If you can rely on the same rules for vampires, or phasers, or ER proceedure, you don't have to spend time providing this exposition. But then once you've seen several epsiodes, these recurring elements become what you take away from the show, more than any particular story: Buffy kickboxing, Hawkeye with a martini, Columbo saying “there's just one thing that bothers me.”
In the episode “The Zeppo” Buffy demonstrates the clever effects that this makes possible. The episode has the same basic structure as Tom Stoppard's Rosencrantz and Guildenstern are Dead. Stoppard follows two minor characters from Hamlet, with Shakespeare's play only occasionally intersecting for brief scenes. Rosencrantz is funny because the audience understands what's happening better than Rosencrantz and Guildenstern do — we've already seen Hamlet, and Stoppard can take advantage of that pre-existing knowledge. In “The Zeppo”, Xander is separated from the other characters for most of the episode, occasionally intersecting with the other Buffy characters who are facing an apocalyptic threat.
But dig it: in “The Zeppo,” the Buffy story that our protagonist intersects with is a story we have never seen. Yet we can follow it because what we do see is full of recurring elements we recognize from other episodes: Willow preparing a magic spell, Buffy and Angel declaring their love for one another, the end of the world averted in secret in tunnels beneath Sunnydale. The show itself is winking at us, saying it knows it falls into these patterns, and then using that admission to tell a different kind of story.