Dead Fish is the story of an aging man named Lynch (Gary Oldman). Lynch works as a sort of criminal jack of all trades. He is a thief, a spy, as well as spending most of his time working as an assassin. His latest job will put him to the ultimate test both physically and mentally as he must travel back to London, England. There he finds that he is not alone in wanting to complete his mission, but has several bizarre groups of criminals and thieves like himself seeking to do it as well. He must be on top of his game if he is to come out the victor and in one piece.