A rogue Multiverse agent goes on a manhunt for alternate versions of himself, getting stronger with each kill. Only the last version of himself, an LASD cop, can stop his crusade before he becomes "The One".
 
One for all and all for one.
 
FUN FACT:  The scenes involving Jet Li fighting himself were shot using Li and a stuntman with a build similar to his. The stuntman's face was painted green so that it could be digitally replaced with Li's face later.