<P> Siren (formerly known as The Deep) is an American television drama series that premiered on Freeform on March 29, 2018 . The first season included 10 episodes . On May 15, 2018, the series was renewed for a 16 - episode second season . </P> <P> The coastal town of Bristol Cove, known for its legend of once being home to mermaids, is turned upside down when a mysterious young woman (Eline Powell) appears and begins wreaking havoc upon the small fishing town to look for her captured sister (Sibongile Mlambo) who was abducted at the hands of the local military . Marine biologists Ben (Alex Roe) and Maddie (Fola Evans - Akingbola) work together to find out who and what drove this primal hunter of the deep sea to land . </P> <Ul> <Li> Alex Roe as Ben Pownall, a marine biologist who helps Ryn and has fallen for her enchanted siren song . </Li> <Li> Eline Powell as Ryn, a strange young mermaid with a dark secret . </Li> <Li> Ian Verdun as Xander McClure, a deep - sea fisherman who seeks to discover the truth . </Li> <Li> Rena Owen as Helen Hawkins, an eccentric woman who seems to know more about sirens than she claims . </Li> <Li> Fola Evans - Akingbola as Maddie Bishop, a marine biologist who is also Ben's girlfriend . </Li> <Li> Sibongile Mlambo as Donna, a mystical and deceptively powerful mermaid who is Ryn's older sister . She was the reason Ryn came to the surface . She is accidentally shot by a vengeful Xander and later perishes from her wound . Her demise caused Aldon Decker to kill himself via drowning . </Li> </Ul> <Li> Alex Roe as Ben Pownall, a marine biologist who helps Ryn and has fallen for her enchanted siren song . </Li>

When does episode 11 of siren come on