my opinion:
vettaiyan movie is a movie which is having a good story,starcast,screenplay, and the movie goes in a mode of investigative thriller and you can see rajini's swag in some shots,the words till now I have typed are only for first half which ends with a interesting interval block.
let me tell about second half-
the movie starts with a good pace and it goes on good,emotional and interesting for 15min after interval,after that you can clearly identify that story goes in a commercial mode where direction went wrong and the point on which story is revolving goes very normal like a normal commercial film.actually movie is dead at second half.my breath taking element in second half is only fahad fasil,his acting and the hug moment between superstar and fahad is good except that the second half goes flat and you cant even relate to the story eventhough the issue is common in our society for every student due to the misdirection and misused star cast and my opinion about second half is
the star cast except fahad every body's acting is not upto the mark.I don't know where went wrong but 1st time I had surprised a superstar's film with unstable acting.
let me give you review as a fan of rajinikanth:
yes I am a fan of rajinikanth,but this movie doesn't give any rajinified movements to me in the theater at 2nd half.1st half it was bit better,you will see rajini in a good cop roll,makeup for talaivar is also not good,even anirudh music doesn't help for thalaivar in mass elements in second half due to misdirection.even anirudh music is not upto the mark at some scenes,maybe he might done his job according to the story I think so,but this doesn't help for the mass scenes.some times for good bgm the scenes and taking with lacking can ruin the interest of the audiene.I can see rajini is suffocating to act at some scenes,may be his health condition is not very good and at some scenes where we need more emotion to be planted in our brain,rajini failed to do that.I can see that he is acting but I can see something is stopping himself from acting maybe if it's his health issue
rating and advice:so the rating i am giving to this movie I.e 3 stars.only for first half and I expect more from second half however you can watch it once in theatre for story and taking in first half and for some rajinified moments in the movie.