"Each human being's head contains a soul. The one remaining riddle of the universe." 
Recovering
 drug addict David Parsons (Christopher Rydell) gets more than he 
bargained for when he rescues anorexic teen Aura Petrescu (Asia Argento)
 from a suicide attempt. Aura is returned home to her parents, where her
 psychic mother, Adriana (Piper Laurie) is holding a seance for rich 
clients. But during the ritual, Adriana channels a recent victim of a 
serial killer called "The Headhunter," who has been leaving headless 
corpses around the city. Aura follows as her parents run into the night 
in a panic, but she is too late - and only sees the killer making off 
with the heads of her parents. Aura finds David for help and together 
they track down the killer. Could it be eccentric Dr. Judd, who is in 
charge of the clinic from which Aura escaped? What did Aura actually see
 that night? Together, David and Aura must uncover the dark, hidden 
secret that links the victims.
Trauma
 dates to 1993 - a time when the taste for gialli had long past and 
people were even getting bored with the predictability of slasher 
flicks. Scream would come along and turn everything on its head 
in only a few short years. But Dario Argento kept plugging away with 
this attempt to return to the glory days of Deep Red by recycling and re-arranging elements from his greatest hits (in that sense, he's like a cinematic Christopher Wren, who would rearrange the same architectural elements in different ways to create different buildings). I think Trauma
 had a lot of potential but was hindered by a few mis-steps. First, 
Argento's muse, Daria Nicolodi isn't in the cast. I suspect that the 
part of Adriana was written for her but the American producers insisted 
on Piper Laurie for her name recognition and horror cred. Second, 
there's the banal, forgettable orchestral score by Pinal Donaggio. 
Trauma would have been 100% improved with a classic Simonetti score. And
 third, the script may have worked by 1975 standards, but more modern 
audiences expect a higher degree of sophistication, better dialogue, and
 script that... y'know... makes sense.
- Character actor Brad Dourif (best known as Grima Wormtounge from The Lord of the Rings) has one scene and he goes full-on Nick Cage crazy with his brief screen time.
- Speaking of, Piper Laurie (who made her name playing crazy moms, such as her Oscar-nominated turn in Carrie) seems to have two speeds: nutso-bonkers and asleep.
- Along with his signature camera tricks, Argento also throws in "butterfly-eye-view." 
- The murderer's weapon of choice is an electric garrotte, which 
tightens a wire that cuts off the victims' heads. It's not exactly the 
same, but this manner of mechanical decapitation is one of the many 
elements borrowed from Deep Red.
- Corey Garvin, who plays Gabriel, the nerdy neighbor kid, continues 
the long giallo tradition of creepy, psychotic children. They sort of 
gloss over it, but he straight-up murders someone in this movie.
- The anorexia angle (which is established and quickly forgotten) was 
inspired by Argento's daugher Anna's own struggle with the disease. 
- Horror movie legend Tom Savini was responsible for Trauma's makeup effects.
What the Hell Am I Watching?
Let's start
 at the beginning: As David reaches over the bridge to rescue Aura, he 
shouts "Stop struggling!" She is doing anything but struggling and, in 
fact, looks on the verge of passing out.
A co-worker 
bluntly asks David if he has done the grownup with Aura and he 
disgustedly scoffs "She's only sixteen!"  But that doesn't stop him from
 making out with her (and probably more) just a few scenes later.
Please enjoy one of the most cheaply-produced dream sequences ever committed to film.
One
 of the ancillary victims not only gets a full name – Nurse Hilda 
Volkman – but news of her death is accompanied by a professional 
black-and-white headshot. I find this hilarious.
Looking
 for Dr. Lloyd, David checks out a seedy local dive bar. Apparently, 
Argento's idea of an urban American bar is an old-timey saloon with dark
 wood paneling and a pianist in the corner banging out some ragtime.
This
 movie's killer is the MacGyver of homicide. When the electric garrotte 
breaks on a victim's necklace, he doesn't panic - he just places the 
stunned victim's head in an open elevator shaft and pushes "down." The 
elevator does the rest, chopping the head off cleanly. The decapitated 
victim is even able so scream before his head hits the ground. Gruesome 
and hilarious.
If they were to make action figures of 
the characters in this movie, I'd want one of the nameless pharmacist 
who punches out David. 
Action Pharmacist!
Stick 
around for the credits, wherein a reggae band performs from the front 
porch of a home near the final crime scene. The camera zooms in on a 
girl swaying to the music while the reggae band fades and the orchestral
 score takes over. It's simply a weird way to end a weird movie.
Fashion Moment
When Dario Argento makes a point 
of showing you an unusual piece of jewelry in the first ten minutes, 
you'd better believe that it's going to be important later on.
And by the way, track marks don't work like that. They're called "track marks" not "randomly spaced marks."