This is the comment copied from the website, i hope this can help you to understand the movie
A writer arrives in Singapore for starting a new life, which is nothing but counting time at dealing tables. His name is Chow Mo-Wan (Leung Chiu-Wai). A mysterious woman, only known as Black Spider, quietly walks into his life and brings back his lost memory, the memory of the time he spent with an married woman named Su Li-Zhen (Maggie Cheung). Black Spider helps the writer to win back his money then he could buy a ticket returning to Hong Kong. She refused to share her past with him, except her name, which is also Su Li-Zhen (Gong Li).
The writer returns to Hong Kong alone and on Christmas Eve, he meet Lu Lu (Lau Kar-ling), another woman from his past, who now has no memory of him. Chow sees a familiar number on the door of Lu Lu's hotel room - 2046. Room 2046 was filled with memory of the days he had with Su Li-Zhen, and is now trashed by Lu Lu's boyfriend CC (Chang Chen).
He moves into Room 2047 to start his life, again as a free-lancer. He met two daughters of the hotel owner (Wang Sum), Wang Jie Wen (Dong Jie) and Wang Jing Wen (Faye Wong). Jing Wen's relationship with her Japanese boyfriend (Kimura Takuya) was not allowed by his father and Jie Wen just started to learn what love was. Then a new tenant, Bai Ling (Zhang Ziyi), moved into 2046 and he picks her up in no time. Just when she shows some real feeling, he immediately excludes her from his life.
He starts writing a new story, titled 2046, for Jing Wen and her boyfriend. In the story, a train departs for 2046 once in a while and people boarded the train would find back their lost memories. No one wanted to leave 2046, except Tak (Kimura Takuya). He falls in love with a senseless robot (Wong Faye), who offered him great joy along the ride. But each time Tak asks her to go with him, the answer is always silence.
2046 was in development when In The Mood For Love was still in progress. It was originally thought as a sequel to it, but is really about a story of its own. Wong Kar-Wai struggled for five years to tell us a story, or a collection of stories, about a dissolute and disillusioned writer and fractions of his experience with six women. Wong Kar-Wai takes us through a thrilling ride, drifting between the writer's memory and his fantasized train journey from 2046. Su Li-Zhen of Singapore is nicely portrayed by Gong Li. She is a con of card game, who is always dressed mysteriously in black. The writer discovers something familiar, which reminds him other Su Li-Zhen from his past. He tries to uncover her secret and lure her into his life but fails. Gong Li's role keeps such great distance away from her early films that we would forget she used to work with Zhang Yimou.
Lu Lu, a showgirl lives in her jealousy, is played by Lau Kar-ling, the girlfriend of Leung Chiu-Wai. She is changing love interest so friendly that no memory is left for the writer, one of so many men she has dated. Later on the train, she is a robot, sexy and senseless.
Faye Wong and Kimura Takuya play a couple of lover who could not be together because of the girl's father. The writer starts to deliver letters for them and later recruits her as his assistance. Something between them blooms but her heart still belongs to someone else. Faye Wong is very impressive as playing a girl in love and a gorgeous robot who knows nothing but serving the train riders. Kimura Takuya does a great job as her Japanese boyfriend, desperately to get the girl she love, and the sole passenger on the train, desperately to leave his memory behind. He is, again and again, asking the robot to come with him, even though there is no hope that she would ever answer.
Zhang Ziyi is ranked number five on the cast list, but she is really the star of 2046, only next to Leung Chiu-Wai. Her character, Bai Ling, is a prostitute, though the film has never made it clear. Her time with the writer is sweet but short. They attempt nothing from each other but quietly starts to grow. She is the women he knows the most and is also the one he least wants to have serious relationship with. Zhang Ziyi skillfully shows us the evolution of her character, a performance breaking-through her past. Now I am really convinced she could play any role she wants.
Chang Chen and Dong Jie only shows up for a couple of minutes, either because their roles are too supporting or because their scenes have been cut. Maggie Cheung, the star of In The Mood For Love, only does a cameo her. 2046 is no longer her story.
2046 is like a lavish feast celebrating the finest arts ever created. Christopher Doyle, Lai Yiu-Fai and Kwan Pun-Leung, the mEn behind the camera lenses, are truly masters of colors, lights and layers. They uses mirrors, glasses, door frames and all other tool he can find, to create illusive images, which makes us to believe the writer's mind only exists in a illusion. From the women's dresses and the hotel literally rusting to dust to the futuristic robot suits and the high tech train, Chang Suk-Ping, the art director and costume designer, masterfully created two drastically different worlds being seamlessly blended into one film. Original scores by Peer Raben and Shigeru Umebayashi and unoriginal music from masters of the past also transform the film into a classic collection of operas.
2046 is Wong Kar-Wai's most stylish work ever. We see his mind travels through time and space, freely and randomly, collecting various pieces of his imagination, to depict a journey of a man. In the end, we see the story returns to the exact point where it started more than two hours before. The only difference is the writer has more memories for feeling sad and we just finished riding a cinematic extravaganza. 2046 is not a film suitable for everyone. Stay, if you are looking for an experience and go, if you are looking for a story. 2046 is very 2046 and 2046 is very Wong Kar-Wai.
After words: The version now showing in China, including Hong Kong, runs about 128 minutes, which is 5 minutes longer than the one screened in Cannes last May. Reportedly, after retuning from Cannes Wong Kar-Wai re-edited the film in attempt to make it more understandable.
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