 According to the film historian and critic Bill Warren , Tenebrae is a typical example of the giallo film genre : " visually extremely stylish , with imaginative , sometimes stunning cinematography " , it presents " mysterious , gruesome murders , often in picturesque locations ; at the end , the identity of the murderer is disclosed in a scene destined to terrify and surprise . " These narrative and stylistic clichés had been introduced years before Argento made his first thriller , 1970 's The Bird with the Crystal Plumage ; most critics point to Mario Bava 's The Girl Who Knew Too Much ( 1963 ) as the original giallo . 
