Do you have to watch both shows to enjoy a crossover episode?

Geek TV fans have several crossovers to look forward to over the coming months. Family Guy will open this autumn’s season with a Simpsons crossover, followed by a Simpsons/Futurama crossover  a few weeks later, in November. But crossovers aren’t just for 25-year-old shows looking for fresh ideas; the first season of The Flash will include a two-hour crossover story with Arrow, following in the grand tradition of spin-off shows using their parent shows to boost viewing figures in the first year also exemplified by Angel/Buffy The Vampire Slayer, Stargate Atlantis/Stargate SG-1 and every Star Trek spin-off pilot except Enterprise. But what if you only watch one of the two shows involved in a crossover episode, and don’t have the time or inclination to catch up on the other (due to the need to go out, go to work, possibly spend some time interacting with other living members of the human race)? Can you still enjoy a crossover episode?

Partly this will depend on what type of crossover episode it is, as they come in two main flavours. The first is usually restricted to a single show and features guest appearances by characters from the other show – presumably, this is how the Simpsons/Futurama crossover will work, considering Futurama has been cancelled (again). These are usually at least comprehensible, on some level, to most viewers, though references and emotional resonances are likely to be missed. The second type is the full plot crossover (the form the Arrow/The Flash crossover will take) in which a story started in one show is concluded in the other. These can be much trickier, especially if the show you watch is the second show – an unresolved plot is one thing, but an in medias res opening that never explains the backstory is quite another.

Crossovers between unrelated shows are usually the first type, characters from one show appearing in another (though there are exceptions; ER and Third Watch did a full plot crossover story during the former’s eighth season/the latter’s third). As such, they are usually fairly comprehensible since they’re written as an episode of one show only, incorporating elements of another, though it may help to have absorbed some knowledge of the second show from the general cultural zeitgeist. X-Cops, for example, is a perfectly comprehensible episode of The X-Files which only requires viewers to know that there are shows out there that follow the police around. With the shoe on the other foot, you’ll get more of the jokes in The Simpsons/The X-Files crossover The Springfield Files if you’ve seen The X-Files, but even just knowing of the show’s existence will ensure most of it makes sense.

Most crossovers of either type, though, occur between shows that openly and obviously share the same universe, and in most cases that means a parent show and a spin-off. (Exceptions might include Star Trek: Deep Space Nine’s Quark’s appearance in Star Trek: Voyager’s pilot – Star Trek is the grandparent show and Star Trek: The Next Generation the parent show, but DS9 and Voyager are both essentially TNG spin-offs, making them sibling shows…?). These also follow the two main basic types.

Guest appearances do sometimes benefit from a bit more knowledge of the parent show. For example, several characters from Cheers made appearances in Frasier, and mostly all that was required was a simple explanation that they were Frasier’s old friends from Boston. His ex-fiancée Diane’s appearance, however, was a little more complicated. Not only did she have the most complex history with Frasier, the plot of her episode revolved around her writing a play based on the characters and setting of Cheers. Without having seen any of the parent show, new viewers might be confused by Frasier’s mounting horror as he watches a preview of a story that paints Diane herself in the most flattering possible light, and skates over his feelings all together.

Most of the time, though, when the crossover is an appearance rather than a fully integrated plot, the writers will make an effort to ensure that the episode makes sense on its own. The main thing that is lost if you haven’t seen the parent show is the emotional impact of the story. You don’t need to know anything about Scotty to enjoy and appreciate TNG’s Relics, but if you’ve never seen an episode of Star Trek you won’t feel the surge of nostalgia brought up by the loving recreation of the Enterprise (no bloody A, B, C or D) bridge.

Full plot crossovers can be trickier. If you only see half of This Year’s Girl, Who Are You? (Buffy The Vampire Slayer), Five by Five, Sanctuary (Angel) and The Yoko Factor (Buffy again) you’ve really only seen half of the story. On the other hand, probably the most comprehensible example of the second type if you don’t watch both shows is Buffy and Angel’s Fool for Love/Darla, because the crossover plot is contained in flashbacks to Spike and Angel’s past. Viewers of both shows get a more complete picture of Spike and Angel’s activities during the Boxer Rebellion (and what look like a continuity error in the Buffy episode is explained in the Angel entry) but the flashbacks in each show support the plot and arc developments of that particular show, with no reference to the other.

One thing worth bearing in mind for the writers of parent show/spin-off crossovers is that the relationships between parent shows and their spin-offs are not all equal. There are some franchises in which you can more or less safely assume that most viewers watching the spin-off are also watching the parent show. There must be people who’ve watched Angel but not Buffy (we’re sure you will let us know in the comments!) but probably not very many, since Angel, Cordelia and later Wesley were major characters in Buffy who spun-off during the parent show’s run and the chief interest in the show, at least early on, came from following those characters into a new setting. In other cases, there’s a greater chance of new viewers watching the spin-off without the parent show. Some fans of later Star Trek series, for example, are not viewers of Star Trek, partly due to the amount of time lapsed between Star Trek and The Next Generation. Frasier operates on a more farce-based kind of humour and in a very different setting from Cheers thanks to the idiosyncratic nature of its main character, so many fans of Frasier may not have seen the parent show.

This is partly why Buffy/Angel crossovers often take the form of plot crossovers, while Star Trek crossovers tend to be guest appearances. It doesn’t especially matter to Voyager fans that it’s Geordie who chases down Chakotay and Kim in Timeless, it just brings a smile to the face of TNG fans (and saves hiring an actor, since Levar Burton also directed the episode). The two slight exceptions are Voyager’s Flashback and DS9’s Trials And Tribbleations, which, although they explain the plot clearly enough, do benefit from a deeper understanding of the context – because these were the thirtieth anniversary celebration episodes, and so they deliberately play more strongly with elements of the original series (and its movies).

What the writers can’t plan for, of course, is that things change over time. Back when Xena: Warrior Princess’ first season aired, presumably most viewers were fans of Hercules: The Legendary Journeys. However, over the years it’s Xena that has gained more critical acclaim and been more important and ground-breaking as a show, making it much more likely that new viewers may give Xena a go but not bother with Hercules. This means there’s a greater chance now that Xena viewers may find themselves a little confused by a Xena/Hercules crossover than the writers could have anticipated.

Then there’s Doctor Who/Torchwood/The Sarah Jane Adventures, which is an interesting case in that some viewers will not have been allowed to see all the shows. Doctor Who is a family show with a particular focus on children, The Sarah Jane Adventures is a children’s show, and Torchwood is a show for grown-ups (‘adult’ doesn’t seem quite the right word). Passionate adult fans will watch all three, but casual viewers are unlikely to watch The Sarah Jane Adventures because it’s too far out of their demographic and on at the wrong time of day, while children may not be allowed to watch Torchwood – which does rather restrict the number of people fully able to appreciate all the crossovers in The Stolen Earth.

In the end, the experience of watching a crossover in a spin-off show is pretty similar to the experience of watching an episode from well into a series’ run without having seen the earlier seasons. Some people prefer to watch a show from the very beginning, ensuring that they get all the in-jokes and emotional nuances, that they can follow every plot without losing the thread, that every surprise makes them jump and every revelation is an eye-opener. Others may prefer to jump in at a later date, especially if the early seasons are less successful or don’t really reflect the direction the show later took (season one of Stargate SG-1, for example, and we’d recommend skipping most of season two of Star Trek Voyager – skip the lizards and it gets a lot better after that). Others simply catch a show on TV or when viewing with a friend at a random point in its run and get interested, following along as best they can (I can tell you from personal experience that the season three finale of The Vampire Diaries may not make a lot of sense if it’s the first episode you ever see, but it’s still a cracking watch). Watching crossovers is a little bit like that. If you don’t watch both shows, you won’t get all the jokes, all the references, or all the emotional nuances, and you may even struggle a bit to understand the plot. But a really great episode of television is still a really great episode of television, whether you catch that cheeky reference to Mulder’s swimming trunks from season two of The X-Files or not.

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