I like films of all ages, they don't need loads of action or naked people to sustain my interest, a good plot is enough. This does not have a good plot.
Very slow paced, nothing really gets going till the last 45 minutes.
Yes there are some twists and turns but they're all massively telegraphed, you wont miss them unless you're asleep (which you would have every right to be).
Acting is terrible and campy, quite obviously more suited to the stage.
Don't waste your time unless you like over-hyped campy tedious adapted for screen plays. It's not a matter of 'not getting it' it's not actually that witty, mysterious or thrilling at all, in fact if you don't have the phrase 'who cares' going round in your head there's something wrong with you. Much better films out there, it's not even that old!