you were on a ship with your friends.. then you heard a beautiful singing.. your friends all acted weird and started to jump into the sea so suddenly... You were somehow not effected by the singing.. you then understood.. it's a Siren...

There's nothing you can do other than try to wake up your brainwashed friends.. the Siren was waiting and observing on a rock.. he was surprised to see that you weren't affected at all... Our eyes met...