This is a rather mediocre giallo, yet another one co-starring Susan Scott and Simon Andreu; though not a Luciano Ercoli film, it would place somewhere between his two DEATH WALKS titles.
The backdrop for the mystery this time around is a dance academy - hence the original title, which translates to DANCE STEPS ON A RAZOR'S BLADE; the English one, then, refers to the fact that the killer is ostensibly lame. Among its roster of artistically-oriented(!) characters is a photographer (Scott), her special-effects technician boyfriend Robert Hoffman, a musician/producer played by Andreu and Anuska Borova as a scoop-seeking female reporter (who has a twin sister, a former dancer whose colleagues are being brutally murdered!). George Martin(!), who plays the Police Inspector, also co-wrote the script with the director; his face seemed oddly familiar to me but, looking at his filmography on the IMDb, I only recognized the fine Spaghetti Western THE RETURN OF RINGO (1965) - which, incidentally, also featured Scott (under her original Spanish name of Nieves Navarro)!
The film provides plenty of red herrings throughout, but the final revelation is so abruptly presented as to be practically unintelligible! As was the case with THE FORBIDDEN PHOTOS OF A LADY ABOVE SUSPICION (1970), Scott is decked out in some horrendous 70s fashions (worst of all an over-sized cap like the one Jack Nicholson - in The Joker's guise - would wear in BATMAN [1989]!). Besides, the film's overall visual style is pretty uninspired (apart from the stalkings, done from the killer's POV), with its eye squarely on the narrative's exploitable elements - witness the numerous wholly gratuitous sex scenes, and even featuring a dance pirouette that culminates in a striptease! The dubbing, too, is among the worst I've had to sit through for this type of film. Roberto Pregadio's score is pretty nice, though - whose main theme, in keeping with the musical elements of the plot, is turned into a recurring motif.