We all have watched Ratatouille a number of times and pretty much enjoyed it. But, did we really miss an important Easter egg?
Any guesses on what made the rat 'remy' so special, that unlike all other rats he can cook, smell and taste? is it because he is "The Gusteau", reborn?
My theory suggests that this might be true.
Remy is a special kind of rat and his speciality lies in 'cooking' that is exactly the skill owned by Gusteau, which made him one of the finest chefs in the world or paris.
In the prologue, we see that 'Anton ego' (a seemingly egoistic food critic) criticizes gusteau's book "anyone can cook" by saying he doesn't think that anyone can do it. Gusteau might be so furious about this, and it's possible that he desperately wanted to prove it. That desperation of his leads him to being reborn as a 'rat'(remy) after his tragic death (reincarnation in many mythologies suggests the reason behind as 'the soul seeking something, revenge or an unfulfilled wish').so he wanted to take revenge on ego by proving him wrong. if a rat can cook 'anyone can cook'.
He also loses a star when ego reviews his food. so, if he impresses him he can get it back, which makes him(or remy) cook ratatouille.
The fact that remy could control 'linguini' just through his hair, and their actions are effortlessly synchronised , is because he is his son and they share the same DNA.
Remy has yet another job of saving his son from skinner. He might not actually know that, but his inner voice says so. The inner voice is the ghost of gusteau that we see throughout the movie. He is frequently reminded by his subconscious 'gusteau' about his job.
Remember when he(spirit of gusteau) introduces everybody in the kitchen to remy, he takes special interest in introducing linguini and asks 'who is that' to which remy says 'he is a nobody', and then gusteau (with a frown) says "not a nobody ,he is also an important part of the kitchen", which might suggest fatherly affection towards his son.
Back in many old movies when a character wants to speak to itself, it is shown that his/her soul comes out and speaks to him, through which we infer that he is speaking to himself. in this movie also pixar incorporates the same but with a little pun. remy talks to himself but we see that he sees the ghost of gusteau (which is his own soul) but not of his rat appearance, which indicates that both are one and the same and he is little comfortable in his human form that he keeps forgetting he is a rat.
Somewhere in his subconscious mind remy knows why he was reincarnated, but logically it can't be true, so he ignores it.but his soul gusteau is constantly trying to make him reach his goal whenever remy seems to divert away. During the scene where remy is left in sewers all alone, we see that it is gusteau's spirit which leads remy to his restaurant, how would the spirit which only knows what remy knows could possibly know the way to his restaurant , given that remy had never been there? it is because remy had some memories of his restaurant from the previous life stored in his Subconscious.
one can guess from the sudden demise of Gusteau (due to one unfavourable review) that he is very much in admiration of his own work. It is the same admiration that remy shows to gusteau at the starting which is basically because he is a self-admirer.
Gusteau is a splendid cook and nobody can replace him except himself. He comes in the form of a rat to lift the spirits of his employees working in his restaurant.The restaurant as per the tradition loses a star when gusteau is dead so his attempts to regain it back brings him back into this world. People are so in love with gusteau's cooking then and they are again in love with remi's cooking now.(get it?) he may change his form but his skill and desire to cook doesn't change.
The pixars original posters for ratatouille shows a tagline 'he is dying to become a chef' which literally happens in the movie. gusteau dies to become a chef, the chef he wanted to prove to ego, the chef that brings back the lost glory of his restaurant, the chef that saves his son from ill fate.
His restaurant when he is alive has a hoarding on the restaurant showing him with cooking tools in his hand.
in the next life the new restaurant shows his rat form with cooking tools in his hand, both the posters indicate the same. This might be a pixar's way of hiding easter eggs.