Kosa – A young woman named Eva Kaidas, working as an investigator, finds herself involved in a mysterious case of a series of crimes on the Curonian Spit. She must uncover the enigmatic murders of innocent young girls, who become victims of an unknown criminal. Eva, along with journalist Roman, embarks on a search to unravel the complex system of the bloodthirsty killer. Along the way, the heroes will face a series of trials and come face to face with their own fears.