Ice Age: Continental Drift is the fourth installment in the Ice Age series, which was started a decade ago by FOX when they tried their hand at animation again after Titan A.E. became a box office bomb. The series follows a group of quite different prehistoric animals and the plot that it follows has been so far a formulaic "go from point A to B" story.
As the title suggests, Ice Age 4's plot revolves around the separation of continents. The herd is separated and while the original trio goes into an adventure overseas, the "half opossum, half mammoth" family tries to reach a rock bridge to meet up there. The film's animation is fantastic (you could hardly say a mainstream animated movie doesn't have terrific CGI) and backgrounds and water effects are beautiful, but the movie's storytelling is too fast paced and there are too many characters for them to develop while the movie lasts.
If the series is too formulaic what is the appeal of this movie? For anyone who has seen the whole series, you'll be happy to know Diego meets a female saber-tooth on the way and Sid is reunited with his sloth family. Amongst the new characters are a crew of pirates that capture the trio while they explore the ocean and become the main antagonists of the film.
The movie is overall quite worth it to watch with your family, but even the third one (which I didn't like a lot) had a better paced storytelling. New characters, in my opinion, don't really display a lot of personality traits other than Granny Sloth, but it is quite the enjoyable flick I would watch a few times on theaters.
The 3D, by the way, is not really worth it and the movie doesn't make use of it correctly. There were some moments when the background looked it was over the characters and that almost gave me a head ache. If you're taking your family to watch the movie don't waste your money on 3D.