Bong (Donnie Yen) is a highly respected hardline cop with a long history of success on dangerous cases. However, his past unexpectedly comes back to haunt him when a sting operation is attacked by a mysterious group of criminals led by Ngo (Nicholas Tse), his former protégé, a talented former officer who had once respected and admired Bong. A terrible mistake three years prior landed him in prison, quickly turning the once rising star into a furious man with a grudge and the will to destroy everyone who had wronged him―including his former mentor.