OT: Halloween movie with sleep as a main topic

"Shadow People" concerning a real life events of those who died from SUNDS, Sudden Unexpected Death Sundrome.

https://en.wikipedia.org/wiki/Sudden_un ... h_syndrome

http://www.imdb.com/title/tt1764647/

A radio talk show host unravels a conspiracy about encounters with mysterious beings known as The Shadow People and their role in the unexplained deaths of several hundred victims in the 1980s.

People who are otherwise thought to be healthy who die in their sleep.