Image Credit: Peter MountainThe simple truth is that sequels tend to be bad. Especially in the last 30 years of blockbuster filmmaking, cinema history has become strewn with miserable follow-ups to brilliant originals. (Exactly why sequels tend to be so bad is a difficult question, since every bad sequel is its own beautiful idiot snowflake.) Now, some scientific proof has arrived: Box Office Quant has posted a nifty Sequel Map that graphs the Rotten Tomatoes critical score of the original movie against the score of the sequel. Check out the result here.

The first thing you notice: The vast majority of sequels scored less well than the original movie (although kudos to Star Trek II: The Wrath of Khan for being the most improved sequel.) The second thing you notice: Good lord, there are a depressing number of sequels. And I’m not just talking about big-budget disappointments like Pirates of the Caribbean: Dead Man’s Chest, either. Anyone remember Texasville, the sequel to The Last Picture Show? Admittedly, the graph only takes into account No. 2 movies — so, no threequels, no long-running franchises, no Casino Royale. (Though let’s be honest: You know that if threequels were on the graph, there’d be an even bigger trend towards mediocrity.)

But wait! Don’t lose hope, sequel-lovers.There’s a huge clump of films at the far end of the graph that were as good, if not better than, the first movie. And we’re talking absolute classics: The Godfather Part II, Aliens, The Empire Strikes Back, The Dark Knight, Toy Story 2, and plenty of other sequels that could easily find their way onto anyone’s Top Ten list. The unifying factor with all those films is that they could only be sequels. From Russia With Love and Spider-Man 2 both reflect lessons learned from the less-than-perfect first films in their franchises. Terminator 2, The Dark Knight, and Empire expanded their pre-existing cinematic universes. The Godfather Part II and Before Sunset looked back longingly (and brutally) at their predecessors.

In the era of Meta-Hollywood — where every movie is a sequel to a prequel to a rebooted, remade, reimagined adaptation of a board game based on a fairy tale — it’s easy to rage against sequels. But what this graph shows is a straightforward (albeit complex) truth: Most sequels are bad, but some sequels are incredible. Which, when you think about it, is pretty true of movies in general.

PopWatchers, find any surprises on the Sequel Map? Am I the only one who loves the fact that Jackass: Number Two apparently got better reviews than Jackass: The Movie? (It’s only because they added in Sean Connery, though.)

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