Take The Descent. Take away 70% of the psychological/claustrophobia scares, add 50% more blood and gore, add a bucket full of horror movies clichés and you've got The Descent Part 2.
I liked the first film; it was different in multiple ways, it didn't rely too much on horror film formula, the cast was all female, the fears were more psychological and slow building, and so forth. It tried something different, it wasn't a work of art but you can't fault them for trying something new. However when I found out that the sequel was based upon the American ending of the filming (as in the 'happier' ending) I had doubts...
The Descent Part 2 takes place 2 days after the first film; a local man finds Sarah, the sole survivor of the horror that happened in The Descent, and takes her to hospital. However the poor woman is traumatised and doesn't remember what happened. When the doctors analyse the blood on her clothes and realise it belongs to her missing friends, the local police decides to take Sarah back down to the caves to find out what happened, and hopefully find her friends.
The director does try hard to recapture the magic of the first film; with the tight tunnels, the fear of both the caves and the creatures that lurk in the darkness working against you. Also with the throwbacks of footage to the former film, the first half starts strongly. But the weakness of the movie shows towards the second half of the film where the clichés come to light. Some characters make stupid decisions (especially the male cop and Sarah becomes slightly out of character towards the end), more emphasis on gore is used to scare the audience, the creatures become over used and predictable, and the ending annoyed me! It contradicts the beginning, makes no sense, cheapens the first film somewhat and leaves it open for another potential sequel...oh goodie...
Plus I didn't connect with cast; in the first film we got to know the group of females as close friends, who they were and such before they entered the cave, so we felt sorry for them when they died and had to turn against each other to survive. But in this film we barely get their first names before someone is killed!
Don't watch this movie if you're expecting it to be as good as the first one, or if you haven't seen the first one at all! It's worth a watch if you're curious to know what happens to the characters and if you like horror films in general so you don't mind seeing the same film tricks over and over again. Worth a watch, then wait and see if there's another sequel.
UPDATE 18TH FEB 2010: According to the Horror Squad website the DVD extras will include audio commentary by the director and numerous actors from the film, deleted scenes, a Making Of, storyboards plus 5.1 sound and 16:9 widescreen for your viewing pleasure.