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Cordelia Shirley Probably. There are references to other things that have happened in the novels, but they're pretty clearly explained, so it wouldn't interfere with your understanding of the plot. However, you might be missing out on a few inside jokes that have been thrown in. I'd recommend reading the rest of the series so you can get to know the characters better (and because it's just an awesome series!), but I don't think it's ENTIRELY necessary!