MellowPlex Score: 5.1/10
Vikram Performance
Review by: All India Roundup
Critic ReviewRating: 5.0 / 10
Iru Mugan scores high on chemistry, history & science and low on entertainment, emotion & drama. Iru Mugan is a one time watch for Vikram performance. Vikram shines in dual roles.
Iru Mugan is a decently entertaining fare
Review by: Only Kollywood
Critic ReviewRating: 6.0 / 10
The first half moves at a good pace with interesting knots which get unveiled at the right places. Except for bad songs placements, there is nothing much to complain about. The interval block is probably the best moment in the film, and does give you a dash of thrill. Into the second half, Anand Shankar concentrates more on the villain character of Akilan but the predictable proceedings and the lack of strong screenplay do affect the flow.
One Dimensional
Review by: IndiaGlitz.com
Critic ReviewRating: 5.0 / 10
Anand Shankar, who gave the neatly packaged ‘Arima Nambi’ has attempted a sci-fi with chemical warfare as the core subject and promises a lot with his set up in the first half only to disappoint with a dragging and illogical second half which pulls down the whole affair to a mediocre level. The much expected Love character is badly etched out and loses fizz very early and this works against the film big time.
Vikram film is not the Onam gift we were hoping for
Review by: indianexpress.com
Critic ReviewRating: 3.0 / 10
Vikram in a double role, Nayanthara and Nithya Menen cannot rescue this sloppily written sci-fi. The saving grace of this Onam release.
Vikram in full form, technically strong too. But script and logic could have been handled better
Review by: Behindwoods
Critic ReviewRating: 5.0 / 10
Iru Mugan has its pluses in the form of technical prowess but the core story and the treatment lets it down. Iru Mugan shines bright at the technical front, but is a little dull on the story and screenplay
'Iru Mugan' review - Lacks speed
Review by: www.moviecrow.com
Critic ReviewRating: 5.5 / 10
The director has spent considerable effort in googling and researching so many scientific concepts. However, the screenplay and scenes fail to evoke interest due to lack of drama and hook. 'Iru Mugan' travels on a low gear at low speed throughout. One would wish 'Iru Mugan' had taken a dose or two of the speed drug shown in the movie.
Vikram 
Nayantara 
Nithya Menen 
Karunakaran 
Nassar 
Thambi Ramaiah 
Riythvika 
Jasper 
R. D. Rajasekhar 
Anand Shankar 
Bhuvan Srinivasan 
Harris Jayaraj