Madness and mayhem in 'Macbeth' can be seen both in the microcosm (the inner world of man) and the macrocosm (the wider universe) after the murder of the god-ordained king, Duncan, by Macbeth. At the microcosmic level, Macbeth shows signs of madness when he hallucinates (the dagger in the air; and the ghost of Banquo) and hears voices (after the murder of Duncan, he hears a voice cry out "Macbeth shall sleep no more"). Lady Macbeth, though she is in control of herself in the first few acts of the play, succumbs to madness in the last act (sleepwalking scene) and ends up committing suicide.
Macbeth also unleashes madness and mayhem upon Scotland when he attempts to rid himself of those who might pose a threat to himself and his decendents. His actions are mad in a metaphorical sense, rather than in a literal sense.
At the macrocosmic level, the murder of Duncan disturbs the ordered universe and unnatural things happen in nature. For instance, it is reported that Duncan's tame horses suddenly turn wild. Other reports describe further disturbances in nature. Imagery of blood and violence contribute to the notion that madness prevails; and that the forces of darkness have displaced goodness and order in the world.