Continuity is a fluid, ever expanding thing. Crossovers help to expand continuities in new and interesting ways. Some crossovers are official, and go both ways. When Detective Munch and the cast from the television series Homicide appeared on Law and Order, the producers of both shows made a decision that from now on, two worlds can now be considered to be one world. However, when Detective Munch appeared on The X-Files, the door, to quote Egon Spengler, doesn’t swing both ways. From now, all the events of the shows Homicide and Law and Order can be considered to have happened in the universe of The X-Files, but all the events of The X-Files didn’t necessarily occur in the universe of Homicide and Law and Order.

This is a keen insight, developed by my friend Daniel Ciora, Esquire. He was reacting to an obscure crossover between the shows Knight Rider and Star Trek. I could explain it, but poobala.com does a much better job. Check it out and come back. My friend, when I pointed this out, was distressed. The imagined purity of our beloved Star Trek was tainted by a reckless attempt at a crossover by well-intentioned writers working for a crap TV show. It wasn’t even the original Knight Rider series, but the knock-off sequel. In the end, he pointed out that Star Trek owes nothing to Knight Rider, and even if all the events of Star Trek happen in the Knight Rider universe, we can still be reasonably confident that the events of Knight Rider did not happen in the universe of Star Trek.

I like to think of this as a one-way crossover. If we were to draw a diagram of the crossovers mentioned above, we would draw a line between Homicide and Law and Order, with an arrow at both ends of the line. In the line that stretches between Homicide and The X-Files, we would have an arrow from Homicide pointing to The X-Files, but no arrow going the other way.

(As an aside, I’ve always been struck by the similarity of this kind of thought to certain ideas in theology, especially syncretism. If we look at the history of the Christian church, we’ll see ideas and movements (such as Mithraism) absorbed into Christianity in a sort of two way crossover, and we’ll see religions such as Voodoo borrowing Christian concepts in a one way crossover. Going further, we could see Judaism as Star Trek: The Original Series, Christianity as Star Trek: The Next Generation, and Islam as Star Trek: Deep Space Nine. But that’s beside the point.)

However, despite my friend’s objections, what’s wrong with Knight Rider being a part of Star Trek’s history? Earlier I’ve made the argument that T.J. Hooker is Captain Kirk’s ancestor, based on their physical similarity. Despite Poobala’s comments to the contrary, there’s no reason to think that the science developed in Knight Rider didn’t result in the kinds of computers and robots seen on Star Trek. Technological similarities between series may indicate they are in the same universe.