Ok ..i thought and i think i got an idea..its not the best -i know - but w.e. i saw to many movies :)
How about a map called dm_cinema or sumthin like that where u're in a cinema , and peeps (sum actors) are "watchin" sumthin like a movie or a fight or ..w.e...and then the zombies come with bazooka`s (rocket laucher`s) and start to ... to ... (hmm) ... to scare people and kill them =D And peeps (actors) have pistols and try to kill zombies (loool) ,but they cant and zombies kill all peeps with bazooka ... or sumtin like that ...
I havent think about a end yet ... but it wud be nc with sum special effects and ... Maybe u/we can make zombies talk or sumthin like that and peeps scream (all that u need is a microphone to record it) ....
Well ..duno..thats 1 idea ;) I told u i saw too many movies and i got crazy ideas but I think with sum hard-workin` players (who wanna do this) this can become a good movie (of course it will take a little - like sum days , but w,e) :D
And we also need a map

to do this
Opinions Opinions =D