Greystone Mansion?
This is one of the movies listed as having done filming at the often used filming site Graystone Mansion, built by oil tycoon Edward Doheny for his son Edward in 1928, in Beverly Hills, California.
https://en.wikipedia.org/wiki/Greystone_Mansion
https://www.google.com/maps/place/905+Loma+Vista+Dr,+Beverly+Hills,+CA+90210/@34.0897001,-118.4020792,301a,35y,39.37t/data=!3m1!1e3!4m6!3m5!1s0x80c2bc22570f6e51:0xf8a10376b6b1d583!8m2!3d34.0919167!4d-118.4014301!16s%2Fg%2F11b8z029wq?entry=ttu
Actually it isn't said which version of Flowers in the Attic was filmed at Greystone.
Does anyone know whether this movie used only the grounds, or showed the exterior of the mansion, or filmed interiors in the mansion?
Does anyone know what fictional building Graystone Mansion was supposed to be, and the fictional location of it?