Mermaid or sirens have been part of the cultural tradition of the sailors during the first expeditions in the western world. The Siren's Myth appeared for a first time with Homer, who described in the Odyssey some singing creatures that lured the enchanted sailors to death. More frequently described with a bird body and a female head, sometimes the female part was extended to torso, with arms prolonged in sturdy claws. In the Latin literature Publius Ovidius Naso presented in the Métamorphoses these creatures. Proposed ethymology for the word "siren" seems to confirm the prerogatives of these creatures, related to magnetism, seduction, charm. The first figuration of Sirens resembling to fish-women was in the second century bc. Hans Christian Andersen provided to leave us the strongest legend of Siren in the well-known fairy tale "The Little Mermaid". Following this story, Sirens are definitely considered as beautiful half-fish women who lived in the bottom of the sea, having a lovely voice to be used when they rise up to allow sweeter the agony of the wrecked sailors. Beyond the Myth, may the Siren really exist? It can be hypothesized that these creatures probably were individuals affected by sirenomelia. In our literature and medical review, we describe the etiology of the disease, and we illustrated the anatomical features of fetuses affected by this pathology using MDCT 3D reconstructions. Syrenomelia is a condition not compatible with the normal life, however nine cases of "mermaid" survived to reconstructive surgery have been reported until now. In our report we also presented a case of survival baby girl affected by sirenomelia, before and after surgery, with correlative radiologic imaging findings. The most important characteristic that seems to allow survival of the affected individuals is the presence of one functional kidney, displaced in pelvis. As so dramatically tragic was the history of the Andersen Little Mermaid, so unattended pleasant would be the destiny of a modern mermaid, who can hope to finally marry her prince, without the risk to "loose her head", as the Copenhagen City's Symbol did in the past years, for a story beyond the Myth.