Help Needed!
 

Hi All

I have been searching for the name of a horror film I saw about 25 years ago but unfortunately I only have the following details...

-Plot was about a satanic cult (I think)
-The end scene involves a girls choir and at the end just before the credits a girls choir dress combusts / catches light and burns
-American made (I think)
-Was made roughly between '75 - '85

I know this isnt a lot to go off but I was young when I saw it! Any help would be appreciated

Regards