Sherry Miles,Celeste Yarnall in The Velvet Vampire (1971)
Sleepy-eyed nice guy Lee Ritter and his vapid, but pretty wife, Susan accept the invitation of mysterious vixen Diane LeFanu to visit her in her secluded desert estate. Tensions arise when the couple, unaware at first that Diane is in reality a centuries-old vampire, realize that they are both objects of the pale temptress' seductions.