The idea of the movie is good, also the special effects. But the plot have some mistakes that is really considerable.

Zelig is full of Allen's style, using a lot of ironic, on the dialogs and the history that he created.
Leonard Zelig is somoene who has the incredible hability to transform himself as the people who's around him (like a Chameleon).
Zelig has a lot of really good jokes, including the soundrack, made for the film, wich have songs called: “Leonard, the Lizard” , “You May Be Six People, But I Love You” and “Chameleon Days”.
The funny thing is that Leonard, who transform himself to feel included, loose his own personality, and in some moments, is completely alone. This is another metaphorical Allen's point of view that can be clearly noticed in the movie.

One of Woody's master piece, Manhattan shows the complexity of the relationships in a simple and funny way (Allen's best charecteristic).
With quick jokes about judaism, the city of new york, relationships, religion and philosophy mixed with the cultural side of Allen, makes this film a classical one.
A film that you will see more than one time.