A former motorcycle gang member, Ki-su, makes a living as a bike messenger. One day after making a delivery to an office building, he witnesses the building blow up. Never suspecting he could have anything to do with the bomb, he moves onto his next job--which is escorting a girl group singer, A-rom, to a TV station. A-rom, it turns out, is an ex-girlfriend from his biker days, and she's none too thrilled to see him either. As she puts a proffered helmet on her head, a timer mechanism is triggered and a countdown clock appears. Ki-su gets a call from a stranger telling him that the helmet is booby-trapped and will blow up if he fails to make a series of deliveries the stranger demands within a fixed time limit. Ki-su manages to make the deliveries, but each turns out to be a bomb. With the police hot on his trail, he races to complete his last mission and stop the timer on the helmet.
Embedded below is the trailer.