Here's an excerpt from the film's description:
In Amalia's mind and body, spiritual and sexual impulses seem to mingle like molecules forming a volatile compound. The object of her own vocation, which is implied more than articulated, is Dr. Jano (Carlos Belloso), a participant in the conference. One day, in the midst of a crowd watching a demonstration of the theremin (an instrument known for its eerie, otherworldly sounds), the doctor rubs up against her, a creepy violation made more so by his morose flirtation with Helena (Mercedes Morán), Amalia's mother, who wears her loneliness like a backless dress.
Sadly, another "eerie" and "otherworldly sounds" reference, but it's exposure... and exposure is good in this stage of World Thereminization :)