Director R. Balki had presented a modern May-September love-story in his debut film Cheeni Kum and in Paa, he decides to portray a tale of father-son-bonding. The clever twist (No doubt inspired by Benjamin Button!) comes from the fact that the son is affected by Progeria – a rare illness causing premature aging and that role is being played by a make-up- transformed Big B!

Raised by a single mother (Vidya Balan) and the old grandmother, Auro (Amitabh in an unbelievable new avatar!) is an intelligent school-boy affected by Progeria. Despite his old, alien-like looks, Auro is quite a popular kid in the school with his gang of chums. After winning a prize in a school-contest from a popular MP (Abhishek Bachchan), Auro becomes his net-buddy and is surprised to know from his mother that the young politician is his father! The MP (unaware of his son's existence) becomes a close friend of Auro, who at his mother's insistence doesn't divulge the secret. Will the father-son relationship ever come out into the open? Will it be accepted by the world? Will Auro get his Maa and Paa back together?

Paa is not a story about Progeria or its challenges. It just uses the medical condition to provide the novelty and it does that quite sensitively. Essentially it is the story of a son born out of wedlock and his bonding with an estranged father. Balki gets the equation right while depicting the father-son interaction when the father is unaware of the real relationship and the son is under oath not to reveal it! The flashback romance and breakup sequences also make their mark perfectly. Balki has a way with getting good performances from his kid-actors and the school-sequences of Auro and his gang are some of the most imaginative and funny ones. But if the film doesn't turn out to be a masterpiece it is because of some ordinary and utterly avoidable politics-heavy scenes sticking out like sore thumb. The toilet humor too could have been given a pass!

What really works for the film is the strength of individual performances. Abhishek and Vidya suit the requirements perfectly, both as the young lovers and as the estranged couple. The grand-mum (with a nickname 'Bum'!) is lovely but Paresh Raval's grand-dad has no much scope. The kids are all fantastic. But the crown jewel is Amitabh as Auro!

Many of his critics had rightly pointed out his reluctance to let go of the white bearded Big B- persona in any of his second innings-roles and here he answers them in some style. We see him as a kid – a thirteen year-old school-student who thanks to Prrogeria looks like an alien! The old withered face, the fallen teeth, the over-sized, vein-riddled hairless head, the weak bespectacled eyes, the stooped shoulders, the gawky walk, the squeaky voice – he is not the Amitabh we know since decades. And yet, underneath that garb he still is the same – the actor with a power to stun with his penetrating performances! The transformation takes away the famous baritone voice and the facial expressions from his armoury but still he manages to convey every subtle emotion through vocal inflections and eye/body gestures. He practically imbibes that school-kid persona in body, soul and spirit! It is one amazing performance!

You could very well watch Paa for this performance alone but thankfully the film also offers much more than that! It is definitely one of the most watchable films of the year.