Think of the best horror sequel you've ever seen. Not a Part 3 or Part 4, but the best direct sequel to a horror film. Halloween 2, Phantasm 2, 28 Weeks Later, Evil Dead 2, and Friday the 13th Part 2 spring to mind, though I'm sure I am forgetting a few others. Now think of the WORST sequel you've ever seen. Nightmare on Elm Street 2, Exorcist II, The Hills Have Eyes Part II (Twice!), A Return to Salem's Lot, Fright Night 2, Poltergeist 2, and the list goes on. It's well-represented fact: sequels are hard. [Rec] 2 not only avoids the pitfalls of those horrible sequels, but, combined with 2007's [Rec], the series should be considered one of the best one-two horror film punches ever.
Like Halloween 2 and Phantasm 2, [Rec] 2 begins minutes after the first film. 15 minutes, in fact. The (ahem) quarantined building from the first film is now being handed over to a small SWAT team (or Grupo Especial de Operaciones in Espanol), who bring along a representative from the Ministry of Health who is not quite who he seems. To say more would give away spoilers, but for any red-blooded horror fan, you can imagine that, despite the best intentions of all involved, things don't work out as planned.
[Rec] 2: Fun For the Whole Family!
Like [Rec], the entire movie is created from "found footage," starting with a SWAT officer as well as individual cameras on the officers' helmets. The movie switches to two different cameras throughout the movie, and each time a new camera is introduced, writer/director Jaume Balaguero and Paco Plaza introduce it as a surprise, the second time more surprising than the first.
When it comes to sequels, it's not just about learning from what you did right the first time, it's also about raising the bar. [Rec] 2 does just that. [Rec] ended with the new reporter (Manuela Velasco) finding that the virus had an unusual link to the Vatican (something that the American remake, Quarantine, ignored completely). Rather than ignore the link, [Rec] 2 explains it, thereby raising the bar again by changing the virus from a simple zombie plague and into something even scarier.
I won't elaborate any further, except to say that watching [Rec] 2 is worth the effort and will be best if you have no preconceived information. I knew very little about the movie and was happily surprised at the quality of the movie and the excellence in execution demonstrated by Balaguero and Plaza. They've done what so many have not done, created an instant classic with a sequel. I'm tempted even to say that [Rec] 2 is better than its predecessor, but there could be no [Rec] 2 without [Rec].
And if you don't buy that, just know that [Rec] 2 is absolutely better than Lost Boys: The Tribe.