In Vivre sa Vie, Anna Karina plays Nana, a shop girl who suddenly decides to become a prostitute, and sensitive to unpredictable emotion. Nana is intimate, much like the act of prostitution itself, and surprising. The audience is not given a reason as to why Nana abandoned Paul or her child for a life of prostitution.
While Nana thinks that it was her choice to become a prostitute, this is not the truth Godard is poking at. The form of the movie makes subtle hints that personal confidence and perseverance is not enough. The American Dream asserts that anyone with motivation can achieve wealth and status, and Vivre sa Vie represents the realistic limitations, at least in France during this time, of such success.
Anna Karina's performance in this film is probably my favorite from her. Her piercing eyes and intelligent readings of others are portrayed flawlessly. She really makes the audience understand that Nana's burden is her own to carry, even if it arose from poor circumstance or fate.
The dark form and congested sound of the film seem to portray a starkly modernist point of view. The anonymity and swallowing nature of urban society seems responsible for creating an indiscriminate atmosphere that Nana becomes enveloped in. It is a surprsing effect of form, and one of the accomplishments of the movie.