Slasher films involve a mysterious psychopathic killer stalking and murdering a sequence of young, weak, and vulnerable victims. Key early influential slasher films include Halloween (1978), which popularized the masked killer, and Friday the 13th (1980), which brought graphic violence and a sequential murder countdown to mainstream audiences. Slasher films typically feature stock characters like the final girl hero who fights the killer, and victims who are often female teens killed after sexual activity. The genre became popular in the 1970s influenced by earlier psychological horror films and continues with remakes and sequels today.