Fai and his three associates lead carefree and playful lives as pickpockets (aka "sparrows" because of their "light touch"). When the mysterious Beauty charms them into stealing a key, the sparrows worry about what they're getting themselves into, but accept the job when Beauty threatens to take her own life.
Mystery builds as the sparrows go forward with their plan. At the rendezvous point, Hollywood Inn, Beauty and the key disappear altogether. It seems Beauty carries many secrets, including her relationship with the reclusive powerful tycoon, Mr. Yen. The sparrows are playing with fire, although this knowledge hardly lessens their intrigue.