Cinematography in psychological horror films has evolved over the decades from the 1920s to the 2000s. Early 1920s films relied on expressionist techniques and focused on Gothic monsters and mad scientists. The 1930s introduced sound and questioned science versus religion. The 1940s saw fewer films due to WWII. Psychological horror emerged in the 1960s with films like Psycho. The 1970s explored family fears and the 1980s brought technological advances in special effects. Serial killer films became popular in the 1990s. Psychological and supernatural films of the 2000s played on future fears and the unknown.