Monica Castillo of RogerEbert.com wrote that director Luis Ortega took liberties with the inspiration story by reimagining Carlos as a gay psychopathic killer, despite a lack of any proof this was true in reality.

Castillo complimented lead actor Lorenzo Ferro's performance as "eerily hollow and effectively scary" but said eventually "the character's eerie coldness leaves the movie feeling shallow.

"[9] For The Canadian Press, David Friend said Ferro's performance evokes "the demonic cuteness of Macaulay Culkin in The Good Son.

He is, in a word, sexy, and not just for his androgynous beauty but for that supposedly masculine glamour of the daredevil, the outlaw who refuses to play by society’s rules.

The site's critics consensus reads: "As unsettling as it is entertaining, El ángel takes an absorbingly stylish look at the horrific exploits of a real-life serial killer.