Alfred Hitchcock was one of the first directors to make thriller films in the 1920s and 1930s, establishing conventions like suspense and mystery that defined the genre. In the late 20th century, thrillers became more graphic with films like Seven and The Silence of the Lambs that established the popular crime thriller subgenre. Common character types in thrillers include detectives solving mysteries, terrorists causing chaos, spies as protagonists or antagonists, and psychopaths as villains.