Each triplet was adopted by a different family in upstate NY who had no knowledge that their baby was a triplet. One brother goes to a small college where he knows no one, but is recognized by returning students. He's then introduced to the young man they thought he was, who turns out to be his identical twin brother.
This amazing reunion makes the papers and is noticed by the mother of a 3rd young man who looks exactly like the twins in the newspaper. The three young men discover they are triplets and find they share many seemingly hard-wired personality traits and preferences.
But the film is far from being a sweet reunion story. The adopted parents of the three triplets soon began to seek answers to many questions, the most pertinent being why they weren't informed their babies had siblings, yet alone, identical triplets. The adoption agency said the triplets were split up because it was unlikely someone would adopt 3 infants, but little other info is given them.
Years later a writer researching twins discovers the triplets' separation as well as the intentional separation of several other sets of twins by the same adoption agency. Little is known about the reason(s) for these separations other than the study of identical twins' and triplets' development in different socio-economic households. The psychologist's study was never published and all the data was sealed until 2066 when all the researchers and uninformed participants are deceased.
Its a very interesting documentary which raises lots of ethical questions, and wants to weigh in on the 'nature versus nurture' question.