 According to Argento expert Thomas Rostock , Tenebrae is filled with rhyming imagery that relates to the film 's exploration of " the dual nature of [ the ] two active murderers " using doubles , inversions , reflections and " re @-@ reflections " . Every major character has at least one double , and the theme extends to objects , locations , actions and events – major and minor . The doubling or mirroring of incidents and objects includes telephone booths , aircraft , homeless men , otherwise @-@ meaningless public brawls in the background , car accidents , typewriters ( literally side @-@ by @-@ side ) , keys , handkerchief , hands caught in doors and the characters themselves . Rostock cites several scenes where characters are set up in frame with their doppelgängers – one such is the first meeting of Peter Neal and Anne with Detectives Giermani and Altieri . McDonagh notes that Argento emphasizes the doubling between Neal and Giermani : " Giermani ... is made to reflect Neal even as Neal appropriates his role as investigator ... the detective / writer and the writer / detective each belittles his other half , as though by being demeaned this inverted reflection could be made to go away . " McDonagh also observes that , in what is arguably the film 's most potent shock , Neal at one point really does make Giermani " go away " , virtually replacing him on screen " in a shot that is as schematically logical as it is logically outrageous . " Earlier , Neal killed a woman who – to his and the audience 's surprise – was not Anne , but Altieri . Tenebrae itself is split almost exactly into two parts . The first half belongs to the murders of Berti ; the second to those of Neal . The two are set up as mirrors of one another . Berti 's killings with a razor are clinical , with " lingering sexualised aggressiveness " , whereas Neal 's ( with an axe ) are crimes of passion committed for personal reasons or out of necessity ; they are swift and to the point . 
