Isis Valverde took singing classes and attended the concerts of axé performers and singers Ivete Sangalo and Claudia Leitte to prepare for her role.
As Sereia, Margareth Menezes (the Police commissioner) herself is an axé singer and performer from Salvador in real life.
Isis Valverde was originally set to have her singing voice dubbed but the producers could not find a singer with a similar timbre to the actress.
Filming begun on October 24, 2012.
Marcos Caruso portrayed a fisherman in O Canto das Sereias (1990), which featured actual sirens/mermaids.