The first whistleblower to go public with charges branding shameless Kevin Spacey a sexual predator is dead — and her grieving family is demanding answers!

Now, in a world exclusive, The National ENQUIRER can reveal investigators have launched a murder probe into Linda Culkin’s mysterious death, while 59-year-old Spacey faces a felony charge of indecent assault and battery for allegedly groping a young man in Nantucket, Massachusetts, in 2016. Click through the gallery above for the shocking details!