Fictional portrayals of psychopaths and sociopaths are some of the most notorious in film and literature but may only vaguely or partly relate to the concept of psychopathy, which is itself used with varying definitions by mental health professionals, criminologists and others. The character may be identified as a diagnosed/assessed psychopath or sociopath within the fictional work itself, or by its creator when discussing their intentions with the work, which might be distinguished from opinions of audiences or critics based only on a character appearing to show traits or behaviors associated with an undefined popular stereotype of psychopathy.

Such characters are often portrayed in an exaggerated fashion and typically in the role of a villain or antihero, where the general characteristics of a psychopath are useful to facilitate conflict and danger. Because the definitions and criteria in the history of psychopathy have varied over the years and continue to change even now, many characters in notable films may have been designed to fall under the category of a psychopath at the time of the film's production or release, but not necessarily in subsequent years. There are several stereotypical images of psychopathy in both lay and professional accounts which only partly overlap and can involve contradictory traits: the charming con artist, the deranged serial killer, the successful corporate psychopath, or the chronic low-level offender with juvenile delinquency. The public concept reflects some combination of fear of the mythical bogeyman, fascination with human evil, and sometimes perhaps envy of people who might appear to go through life unencumbered by the same levels of guilt, anguish or insecurity.

For a more comprehensive film list, see List of films featuring psychopaths and sociopaths

In the 19th century the diagnostic categories of monomania or moral insanity (the word 'moral' then meant either emotional or ethical) made their way into works of literature, covering numerous eccentricities, obsessions or breakdowns—and sometimes acts of apparently senseless criminality, occasionally violent. This period also saw the rise of crime fiction such as sensation novels, where often someone in a local community who appeared normal would turn out to be criminally insane, and detective novels, playing on increasing anxieties about the characters of people in the newly expanding and diversifying industrial cities. The term 'psychopath' came into use in the late 19th century (as did the term it would often be confused with, psychotic), and also spanned a very wide range of conditions (etymologically and originally equivalent to 'mentally ill'). Nevertheless, an early rise to prominence followed its use in a Russian trial between 1883 and 1885 concerning a child murder, contributing to the release of a probable false confessor while the original suspect was found guilty. 'Psychopaths' began to appear in vaudevilles, ditties (songs) and press articles. The psychopathy defense was reported internationally as having enabled a remorseless female child killer to go free, a usage still quoted in dictionaries today.

'Degenerates' were also depicted in popular fiction of the 19th through to mid 20th century, sometimes in similar ways to the modern usages of the concept of psychopaths, sometimes being cited as a cause of psychopathy. The concept fell into disrepute due partly to its use by the Nazis to justify eradicating their opposition.

The meaning gradually narrowed, initially as 'psychopathic inferiors' covering all of what today might be called personality disorders and various other conditions, then intertwining with the terminology of the 'sociopath' (and eventually antisocial personality disorder), though psychopathy remained variously defined in both broad and narrow ways.

Early representations of psychopaths in film were often caricatured as sadistic, unpredictable, sexually depraved, and emotionally unstable (manic) characters with a compulsion to engage in random violence and destruction, usually with a series of bizarre mannerisms such as giggling, laughing, or facial tics. Up until the late 1950s, cinematic conventions usually relegated the psychopath to roles of genre villains such as gangsters, mad scientists, supervillains, and many types of generic criminals. Examples of this type are Pinkie Brown (Richard Attenborough) in Brighton Rock, Tommy Udo (Richard Widmark) in Kiss of Death, Cody Jarrett (James Cagney) in White Heat, and Antonio 'Tony' Camonte (Paul Muni) in the 1932 version of Scarface. Homosexuals were also referred to as psychopaths under the broad definition then in use; the American Psychiatric Association in the first Diagnostic and Statistical Manual of Mental Disorders in 1952 would list it under 'sociopathic personality disturbance'.

One exceptional depiction in this period was the character of child murderer Hans Beckert (Peter Lorre) in the 1931 Fritz Lang film M. Lorre portrays Beckert as an outwardly unremarkable man tormented by a compulsion to ritualistically murder children. A German film (allegedly based on the real life serial killer Peter Kürten), it was released in America in 1933 and has been seen as indicative of a turning point in American media depictions of psychopaths. Until the 1930s psychiatrists typically applied the diagnosis to unemployed males or 'hypersexual' women, but several psychiatric, cultural and economic trends, together with sex crime panics, converged to transform the popular psychopath into a violent, male, sexual deviant or criminal—a threat to innocence, gender roles and the social order.