Just my observation [SPOILERS]
Hey guys, I just saw the movie today and must say that I am pretty impressed by Bollywood's brave attempts to reach great heights.
But one thing is not clear though, if the calls he got were actually his recordings, how on earth did he expect to take the pills the first time at exact 5 AM? It was like the Karthik on phone knew that the other Karthik was going to take the tablets at exact 5AM and so had left a recorded message.
Other than this one glitch, the movie was near PERFECTION :)
I give this movie 8/10 overall!!