The film is credited with coining the term catfishing: a type of deceptive activity involving a person creating a fake social networking presence for nefarious purposes.

As they arrive at the house, Angela takes some time to answer the door, but is welcoming and seems happy to finally meet Nev in person.

As he sits for a drawing, Angela confesses that the various Facebook profiles were all maintained by her, but that through her friendship with Nev, she had reconnected with the world of painting, which had been her passion before she sacrificed her career to marry Vince—who has two severely mentally disabled children who require constant care.

Through a conversation with Vince himself, the siblings learn that Angela had told him (falsely) that Nev was paying for her paintings, and that he had encouraged her to seize the opportunity to have him as a patron.

On-screen text then informs the viewer that Angela did not have cancer, there was no Megan at the downstate rehab facility, and she doesn't know the girl in the pictures.

It was revealed later that the girl in the pictures was Aimee Gonzales, a professional model and photographer, who lives in Vancouver, Washington, with her husband and two children.

In the film, Vince, the husband of the "catfish", relays a story of how, when live cod were shipped to Asia from North America, the fish's inactivity in their tanks resulted in only mushy flesh reaching the destination.

A month after the film's theatrical release, Wesselman-Pierce was interviewed on ABC's 20/20,[14][15] and the Los Angeles Times ran a profile on her.

[16] A year later, The Mining Journal revisited her story in a two-part profile, highlighting Wesselman-Pierce's involvement with the North of the 45th Parallel 2011 exhibition at the DeVos Art Museum on the campus of Northern Michigan University.

[10][14][19][20][21] Kyle Buchanan of Movieline questions why the filmmakers would begin obsessively documenting Nev's online relationship so early on, and argues that it is highly improbable that media-savvy professionals like the Schulmans and Joost would not use the Internet to research Megan and her family before meeting them.

[25] The Schulmans teamed up with MTV to produce a reality television series similar to the idea of the documentary but which focuses on the lives of others who have been entangled in an online relationship with another person.

The site's consensus being "Catfish may tread the line between real-life drama and crass exploitation a little too unsteadily for some viewers' tastes, but its timely premise and tightly wound mystery make for a gripping documentary".

[29] Time magazine did a full-page article, written by Mary Pols in a September 2010 issue, saying "as you watch Catfish, squirming in anticipation of the trouble that must lie ahead―why else would this be a movie?―you're likely to think this is the real face of social networking.

"[31] John DeFore of The Hollywood Reporter called Catfish "jaw-dropping" and "crowd-pleasing", but said that it "will require clever marketing in order to preserve the surprises at its core.