One question? Since David was Tanya's bio-Dad, would she not have looked part Asian? Yet you don't describe her that way. Obviously, that wouldn't have caused her to conclude that David was her father, given the billion or so males that fit that description, but it's a bit odd that she was unaware of some Asian heritage.
.
That's a point that I wrestled with, and while the result may not be 100% satisfactory, I included several references that kind of deal with that issue.
At the very beginning of the flashback I tell David's family history, which includes a reference that his grandfather went to Russia in his youth and married a 'sylphlike Russian beauty.' So David has some Western blood in his gene pool, making it not impossible that his offspring, even if he had coupled with an Asian woman, might have some western features. If he coupled with a non-Asian women, it is possible that
I also mentioned a couple of times that Tanya's eyes had an unusual (and undefined) quality to them. And that her skin was tanned, tawny, etc. words that could alert the reader that her complexion is not western-white.
From the first scene
"It was an arresting shade of blonde, darker and richer than the pale tresses of Scandinavian girls...."
"There was something in the girl’s features that hinted of mystery and a sultriness that hinted at exotic parentage, and possibly even mixed blood. Perhaps it was her sculpted cheekbones, or the elegant eyelashes that invited a man's glance deep into the bewitchingly dark irises of her brown eyes."
In that same first scene David was described as wearing sunglasses, and at the beginning of the scene in which the three men are watching Tanya and Don Roberto's daughter, I wrote
"The tall, lean colonel, his sunglasses having been traded for eyeglasses with unusually thick lenses, answered the door and beckoned for them to enter." And I mentioned that he wore glasses here and there throughout the story. I also mentioned a couple of times that he had trouble punching the buttons on his hand-held.
So there were a few Agatha Christie-ish hints in the text. Admittedly they are not easy to see/remember when a story's installments are published over the space of a month.
The father-daughter point you raise is curious. But my story had never been published anywhere before, and I think I'd only shown it to one or two fans, so I am happy to absolve you of the taint of plagiarism.
I confess that I'm a disappointed that nobody has mentioned the 'revelation scene.' I thought then, and think now, that it is probably the best passage I've ever written.
{SPOILER ALERT -- Do not read if you haven't finished the story}
David Chao felt his head begin to spin at this revelation. “But if Tony Cannizzaro was not your father, then who …”
“I don’t know,” said Tanya Spencer. Nor did she know why this strange conversation had begun to drain the vindictiveness from her erstwhile tormentor. But since it had, she decided that, like Scheherazade, her best chance at survival was to keep talking.
“But I can tell you this," she went on. My mother told me once, with tears in her eyes, that aside from Tony, she had only slept with one other man before she met Tom Spencer, my step-father. That she had been with him only once. And that she had made a mistake for which she could never forgive herself. Just thinking about him seemed to upset her greatly. She never spoke of him again.”
As she spoke those words Tanya noticed that the mastermind of her subjugation had turned deathly pale. “Are … are you… are you all right?”
David Chao had pressed his hands to his face, knocking his glasses to the floor, where they lay at his feet. He rocked slowly back and forth in the chair, his chest heaving silently as if he were suffocating in an airless world. His right hand, his maimed hand, shook uncontrollably.
Mystified by the colonel's agitation, and comforted by the fact that his thin-lipped ferocity had spent itself, Tanya continued to search her memory. “I remember … it was a Thanksgiving morning when I was about twelve or thirteen when she told me about my father. She was sitting at the kitchen table chopping celery and onions for the stuffing while she told me -- I can still see the tears from the onions streaming down her face. And … it was the strangest thing: when she had finished telling me that Tony was not my father, she began whispering the names of the elements. You know, in chemistry. She …"
Tanya was interrupted by a muffled moan coming from her tormentor that seemed to rise up from the very depths of his soul.
"…she had begun to teach them to me when I was eight or nine, telling me that it was like a second set of ABC’s. Hydrogen, Helium, Lithium, Beryllium, Boron …”
“Carbon, Nitrogen, Oxygen …” David Chao's hushed, half-strangled voice joined Tanya's in an eerily-echoing harmony.
Tanya Spencer glanced up quizzically at David Chao who had begun to move toward her with an anguished expression on his face. “Oh, you know them too?” she murmured.