Movies you found to be incomprehensible?

I had to watch CHINATOWN a couple of times before I got it. Now it's my favorite movie.
Same thing with MULHOLLAND DRIVE. Except I still couldn't figure it out and had to look for explanations online. Now I'm absolutely mesmerized by it.
The MOST incomprehensible movie for me though is LAST YEAR AT MARIENBAD. I've looked for explanations online for this one but it appears that NOBODY can figure it out.