Despite churning them out at an alarmingly high rate on an annual basis, Hollywood is incredibly hit-or-miss when it comes to delivering genuinely good sequels. Some of the best ever made learn from the mistakes of their predecessors, improving upon the first movie's weaknesses to craft something familiar, yet entirely different and ultimately much better. Think The Dark Knight, Dawn of the Planet of the Apes, The Bourne Supremacy and Weekend at Bernie's 2.
Other times, the studios are content to simply hit 'Ctrl C + Ctrl V' on the script for a hit movie, change a few locations or lines of dialogue here and there, and simply do the same old thing again because if it worked once, the chances are it'll work again. And it does, frequently, forcing audiences to sit through the likes of The Hangover Part II, Taken 2 and Ocean's Twelve wondering where that creeping sense of deja vu is coming from.
Reinventing the wheel is key to franchise filmmaking, as it manages to extend the shelf-life of a popular brand without veering too far away from what made the brand popular in the first place. However, there have been plenty of sequels that are completely unrecognizable from the movies that launched their respective franchises, and the results can quite often be incredibly hit or miss.
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