*Syrena is a major character from Pirates of the Caribbean: On Stranger Tides portrayed by French-Spanish actress Àstrid Bergès-Frisbey. She is a beautiful, enigmatic mermaid who swims against the tide of her more lethally-minded sisters of the sea. Throughout the film, Syrena develops a loving relationship with Philip Swift, while being held captive by the power-lusting Blackbeard.

A beautiful, enigmatic mermaid who swims against the tide of her more lethally-minded sisters of the sea. Mystery surrounds the mermaid Syrena, even down to her true name, for "Syrena" is only what she's called by missionary Philip Swift during her captivity by Blackbeard. After her fellow mermaids attack Blackbeard's crew at Whitecap Bay, Syrena and Philip begin to recognize a quality in each other that draws them together, allowing them to become allies against a common enemy in Blackbeard. Each discover more of their true beings, but risk their lives when they listen to the sounds of their hearts.

Not much is known about Syrena's early life. Syrena wasn't a typical mermaid; while the other mermaids at Whitecap Bay are quite dangerous, she was rather timid, though she appeared to be noticeably younger and less experienced with the world at large than her "sisters".

Other than being hostile when the pirates captured her at Whitecap Bay, Syrena displayed no traits of vicious behavior and does not attempt to kill any human, or even show the desire to, even though she did hiss at her captors, showing at least some hostility. It is unknown if she ever displayed behavior like her sister mermaids in the past and it changed because of what she sensed in Philip, or if she was different all along from the other mermaids and never was vicious. She has all the skills of a mermaid, but uses them to save Phillip's life when a lighthouse exploded and debris nearly fell on him, instead of drowning him. She fell in love with Phillip, who saved her life, making her the only known mermaid ever to fall in love with a human.*