First of all, answer these questions to yourself.
1) Do you like Pirates, and the general pirate craze?
2) Did you like Dead Man's Chest?
If the answer to both of those is yes, then you'll definitely at least enjoy At World's End. If any of the answers were no, then you'd best steer clear of this.
I really enjoyed this film. Sure, it's not going to win any awards for the best film ever [maybe the most commercially successful?], but if you just go with its crazy logic and over-complicated plot, then you're likely to have a pretty good time. It's better than the second, partly because it always feels like it's heading to some sort of destination - what with the pirate lords being brought together for a final showdown with the East India Trading Co. - no matter how long it has to be, or how convoluted the plot becomes.
At World's End works best when viewed as "Dead Man's Chest Pt. 2", because that's what it essentially is. After Jack's fate at the end of the last film, lots of this one is spent bringing him back. including a wonderfully trippy sequence of Jack inside Davy Jones' Locker, some amazing CGI landscapes and mythology a-plenty. There were many more minor characters in Dead Man's Chest which, if they had been cut out, would have made that film flow more easily, and would have made it shorter. However, many of these characters have real purpose in this film, giving a better appreciation for the slightly less-enjoyable second installment [which I actually really liked].
The plot of this film, for the most part, is a twisted, sloppy mess. It starts off simply, but soon there are so many betrayals and double crossings that you find yourself concentrating so hard that you can't remember each character's objective and need for Davy's heart. By the end, this doesn't really matter, as things even out more, and there's less back-stabbing. There are some real character developments [especially towards the end], and [whilst being very long] feels more rounded as a whole. It is much more serious than the second, with only Captain Jack and Monkey Jack to lighten the sombre mood. It also has one of the most hideously misjudged openings for a [supposedly] family film - if I were you, I'd leave the kids behind. In parts it is surprisingly violent for a 12A, giving the impression that either the BBFC have gone soft, or Disney asked for a lower rating to attract a bigger audience.
Orlando Bloom is much better in this film - his character is a lot more likeable, after all his whining and moaning in Dead Man's Chest, and Keira Knightley's character is given a much more impressive part this time around. But it's Depp's Captain Jack Sparrow and Geoffrey Rush's wonderfully unhinged Barbossa who really steal the show.
We learn a lot more about Davy Jones' past, and the mythology of the Pirates world in this film, which makes the films seem a lot more involving. Davy Jones looks fantastic once again - it's amazing what is capable using CGI these days. Not often do barnacled evil sea captains with a squiddy face/beard look this alive.
The whole film leads up to an incredible, hugely enjoyable climatic battle, which sees the pirates facing off against the East India Trading Co. and Davy Jones. It's a very exciting, involving sequence, which tops many other scenes from recent blockbusters. I was actually surprised at how much I liked this film and how much I loved the final showdown. I'm not going to ruin it - but make sure you see it!
So, to conclude, this film is better than Dead Man's Chest [which will seem better when you've seen this film], but not as good as the original. To me, it never felt as long as its 168 minutes, and it works surprisingly well. It's not the best film ever made, and it isn't going to be loved by everyone, but, hell, I went out and genuinely enjoyed this film. But, make sure you see the second one again before you go to see this!
Genre Value: 4/5
Entertainment Value: 3.5/5
Overall Rating: 3.5/5