Horror thriller directed and staged very well by Larraz who, through aesthetic care and visual strength, manages to provide tension and atmosphere.
Valerie is a young model who witnesses a murder together with her boyfriend Terry , but while she manages to escape her boyfriend will remain missing, amid anxiety, the murderer who shows he knows where Valerie lives, she will meet and fall in love with Paul, who together with his "aunt" designs and makes masks, which it's already saying something given the object in question and what it means, plus, Larraz's trademark, Paul and his aunt have a rather disturbingly morbid relationship.
The Bavian influences are noticeable, it's always a nice see, many blues, purples and reds that embellish the staging, the photography and manage to create atmosphere.
Valerie's initial escape at night, with the photography all in blue, the girl in the car junkyard between the fog provides an excellent sequence.

Blue is a very present color in the film, Larraz inserts it to create anxiety, the many night scenes are excellent, the sequence where Valerie climbs the stairs and the the camera moves backwards with slow camera movements until it shows the entrance of a man.

There is no shortage of subjective shots typical of the genre, the killer who advances but also Valerie herself who secretly at the beginning of the film observes the murder even if she is unable to see, understand who the killer is.
Interesting how Valerie, a model, is photographed, her images are included in albums, therefore she is a girl in "sight" concept, that of sight, of seeing, recalled precisely from the subjective shots of Valerie who saw the murder but not the murderer.

The eccentric new neighbor Horby, has a disturbing aura, raises pigeons, directed by Larraz He first shows them fluttering but then gives various details of the caged birds to symbolize how Valierie is trapped in a story of blood.
Paul himself, in his house, has a canary in a cage, again to underline the condition of the protagonist .
The third act is beautiful, Valerie, seeing everything that happens, decides to leave home, so she will return to the house at the beginning of the film, without her knowing since it was night and she doesn't remember the place of the murder.< 4>

Larraz shows off excellent visual quality here, the references to Bava are numerous, blue, red, purple mixing in the scenes.

The detail of the Leopard makes Valerie understand that the house is the same as the initial murder, the photographer is on blue, disturbing, the sequence of the protagonist climbing the stairs accompanied by camera movements with the omnipresent blue color that mixes with the reds is highly atmospheric.
The appearance of the Paul's aunt, at the end of the corridor, with that blue mixed purple photograph with the reds now present since Valerie is now discovering the previous victims and the extent of the killer, the scene is great and impactful.
It's excellent even the scene at the end of Paul sitting with his leather glove wrapped in a purple light to immortalize the moment.
Horror thriller with excellent atmospheres that speaks through images rather than through the narrative and the characters themselves , the sequences that Larraz demonstrates his ability to transpose to make the genre and its dynamics work.