An experimental submarine, the "Siren II", with a very experienced crew is sent to find out what happened to the "Siren I" after it mysteriously dissapeared in a submarine rift. Things go awry when they begin to find things that shouldn't be there...
Miriam promises her lovers the gift of eternal life, but John, her companion for centuries, suddenly discovers that he is getting old minute by minute, so he looks for Dr. Sarah Roberts, a researcher on the mechanisms of aging, and asks her for help.