Catfish

Everything About Fiction You Never Wanted to Know.
"And there are those people who are catfish in life. And they keep you on your toes. They keep you guessing, they keep you thinking, they keep you fresh. "
Vince Pierce, Abby's father.

The Other Wiki tells us that "Catfish is a 2010 American documentary film directed by Henry Joost and Ariel Schulman."

Nev is a photographer living with his brother Ariel and his best friend Joost, two amateur film makers. After one of Nev's photos is featured in a newspaper, he is sent a painting of his photo by 8 year old Abby. Abby is eloquent and gifted for her age and she and Nev begin talking, first through letters then through Facebook. At this point Ariel and Joost begin recording this relationship hoping to create a Documentary about Abby. Eventually Nev's correspondence extends to include Abby's family, including her mother Angela and her half-sister Megan. As Nev and Megan begin to develop a relationship, Nev, Ariel and Joost decide to expand the documentary to be about New Media relationships, especially the budding romance between Nev and Megan.

Tropes used in Catfish include: