Ignore the synopses about the "futuristic setting" etc etc, because 2046 really picks up right where Wong Kar Wai's sensuous and evocative In The Mood For Love left off. Chow Mo-wan (reprised by Tony Leung) is still trying to come to grips with his relationship with Su Li-zhen. Emotionally bereft, his personal and professional lives get stuck in a rut. Chow ends up writing smutty pulp fiction and newspaper articles in between constant womanising and carousing.
The film centres on his relationships with a few of these women in his life -- a clear invitation to compare and contrast these relationships with each other (and of course, with the ones in ITMFL and DOBW) -- and on the story he writes, the eponymously-titled "2046" which is a thinly-veiled allegory of Chow's own emotional stagnation.
Most of 2046's weakness derives from the huge emotional and narrative debts it owes to Days of Being Wild and In the Mood for Love. If you have not seen DOBW, you could probably still get by. But if you have not seen ITMFL, 2046 will probably make little sense and resonate even less. For instance, the sections with Lulu (played by Carina Lau) and Su Li-zhen (played by Gong Li) are too brief to make any real impression on the audience unless you've already seen DOBW and ITMFL. Carina Lau does well, but it's Gong Li who somehow exudes grace and dignity far beyond the confines of her brief role. In fact I feel she overshadows even Tony Leung, who gives an excellent performance here.
Most the screen time is devoted to the relationships Chow has with between Bai Ling (Zhang Ziyi) and Jingwen (Faye Wong). Zhang pulls off her role well, but it's not very much different from the impetuous, wild child roles she's played in almost all of her previous movies. The woman is in serious danger of being typecast. Faye Wong spends most her time looking cute with those heartbreakingly large eyes -- especially when she's playing an android in Chow's novel. To be fair, she doesn't get a lot of character development. Kimura Takuya who plays Jingwen's lover and Chow's persona in the novel Chow writes, gets even less.
The best parts of the film are the narrative structure and the visuals. 2046 jumps between past and present (and Chow's imagined future), mimicking how people recollect memories. This isn't confusing however, so long as you're paying attention. With cinematography and costuming by the same folks who brought us ITMFL, Wong recreates his sensuous, almost decadent 1960s once again and populates with a host of frustrated, alienated individuals. However, 2046 lacks the emotional resonance and intimacy that ITML, or even DOBW, has.