Dead Man's Chest is the second film in the Pirates Of The Caribbean series, this is also basiclly the start of the second story in the Pirates Of The Caribbean universe.
I personally thought it was a great film and as sequel goes, it wasn't a bad one. It basiclly starts the new story so you don't really need to of seen the first one to get it, but the first one is the best out of all 3 so I would recommend it. The first part of the new story basiclly sets the theme for the final film (3rd now as a 4th is confirmed) and gets you into the story by introducting some new characters. When you watch this and the 3rd one it's good, but on it's own, the film is pointless, but as a series it rules, which is why I like it. I felt this was a great sequel and again, is acted well and has some good special effects, just like the first.