The first hour in the theater pretty effectively proved so. It was going nowhere. The crux of the first 60 minutes is really just Beera (Abhishek) kidnapping the police inspector's wife Ragini (Aishwarya) and ill treating her. Why? You have to sit and endure (i.e., if you manage to last) until the second leg of the movie to find that out. No exaggerations here, but I saw people leave the theatre within the first 45 minutes.
The stuff I had to endure, though, made me wonder (there was loads of time to think :D) what was going on in Mani's mind while creating this masterpiece. The second half was relatively a breather, for it finally gets to the story.
If you like forests, rivers, cliffs, mountains, watch Raavan!