Great movie but not a masterpiece because of strange ending

Rating: 8/10 (2 December 2012)

A very good movie about the life of rich people who do nothing for their money, get bored and seek extreme sensations to get rid of boredom. The acting is great, and there are some terrific scenes. It's well worth watching and you'll find yourself thinking about this moving for a day or two after you've watched it.
The ending however left me with a strange feeling. I'd expect this movie to go on for like 15 more minutes and give some explanation: did he really kill those people? What of what the spectator has seen is true and what's the main character's imagination? I went to IMDb to read reviews to clear this up since I thought maybe I've skipped or misunderstood something. But indeed, the author just doesn't give an answer and like some guys say, it's all the same if the character actually killed or just imagined killing. Well, this is OK but the ending is still too abrupt. If the author wanted us to think that there is no difference if he killed or not, he should have chewed on this for some more time in the ending. I mean it's OK if the film leaves me guessing, but in this case it's just too much guessing and guessing in a slightly wrong area (not the moral or conceptual things but just unexpectedly missing parts in the plot).