Linda Blair: Good Genes or Good Docs?

Linda Blair has devilishly good looks!

Here’s a 20-year-old version of the iconic ‘Exorcist’ star at a party in New York City back in 1979 (left) and 37 years later ... the Golden Globe winning actress -- who’s embracing the Halloween spirit -- last month at Universal Studios Hollywood (right).

Head-turning!

The question is ...