The most obvious - his accent (other than his eye color)

Who would believe that someone would DEVELOP such a huge accent in less than 5 years. His own MOTHER TONGUE.

I spoke Catalonian since I was 7. I haven't spoken it in over 25 years. Do I understand it still? Of course. Am I still fluent in it? Sorta. Do I have an accent when I do? Obviously not, how could I.

A 13 year-old? That's SETTLED in real hard. I can believe a heartbroken family would want to believe any far-fetched lie (drug that changes eye color? sure!), specially if they had a drug-abuse history. But all those "details" should add up after a while.

And any authority could not just believe the eye thing, I am sorry. Thank goodness someone in this "documentary" talked with some sense. I am of course referring to Dr Perry with the Texas Children's Hospital in Houston, who saw from the second Frédéric opened his mouth that the man posing as Nicholas couldn't possibly be an american.

The blaming the family angle was pretty much all Frédéric's narrative. But then there was Nancy Fischer, the FBI lady... Which, to me, seemed a bit like she was going along with the story to cover up her own incompetence. I have a hard time believing she is an actual FBI agent, seems really unprofessional. Almost as a secretary was promoted for the day to pose for the cameras.

To me it is a calculated twist to give us a taste of his con ways, and leave us feeling a bit cheated ourselves.