One dark night| at water's edge| a family of musicians encounter aquatic sirens Silver and Golden. After assuring the family that they won't eat them up| the winsome sirens are recruited to join the Figs and Dates band at a neon-lit Warsaw dance club. When Silver becomes romantically entangled with beautiful blonde bassist Mietek| the more cunning Golden| who cannot escape her bloodthirsty nature| worries that her sister's relationship will doom their shared dream of swimming to a new life in America.