The opening scene of "Martial Angels" takes place during a lavish party. A leather dressed girl Cat (Shu Qi) moves through the crowd in search of an expensive necklace. She's guided via an earpiece by another girl, Monkey (Sandra Ng), and watched over by a third girl Octopussy (Kelly Lin). When she approaches the girl wearing the necklace she discovers that another thief is ahead of her. A guy called Lok Chi Yang (Julian Cheung). He leaves the party with this girl and Cat follows. Later when she once again is within reach of the necklace a voice stops her. Chi Yang is there waiting for her. He tells her that the necklace is fake, and that the real one is hidden in a safety box on the bottom of a swimming pool. This is practically love at first sight, and Cat agrees to join forces with Chi Yang. Together they break into the vault. They get the necklace and Chi Yang manages to steal a kiss before they make their elaborate getaway.
After the daring opening heist we're treated to a James Bond like credits sequence, where the actors' names appear, projected over a naked body, intercut with shots of them standing in or emerging from a swimming pool. Lovely.
When we return to the story, it's been 3 years since Cat broke up with Chi Yang. She's now a secretary for a software firm, but she keeps dreaming of him. In flashback Chi Yang's growing obsession with stealing is revealed, and this was apparently the cause of their breakup.
After a hard days work she meets up with Octopussy again, and the two contemplate how their lives have turned out. Later when they reach Cat's apartment the place is attacked by two white guys (who naturally get their asses kicked in a few seconds). They claim to be from the Russian mob. They show Cat a videotape with Chi Yang and and the head of the Russian mob, Parocov. He has captured Chi Yang to force Cat to steal an important piece of software from the firm where she works. If she doesn't, he dies.
Cat must save her ex-boyfriend from the Russians, and so she gathers the angels again, for one more job.