A new documentary coming to Hulu and Disney+ (depending on your region) this month delves into a catfishing ordeal that Canadian twins Tegan and Sara experienced more than a decade ago and kept secret for years.

Taking advantage of the twins' willingness to interact online, someone began to impersonate Tegan to a frighteningly accurate degree, starting friendships and even relationships with members of the fan community. The messages exchanged would often be very personal, even explicit in some cases, but any doubts fans may have had were largely dispelled by the fact that "Tegan" had access to more than enough information about the real Quins to come across as convincing.

As revealed in the documentary, it's only when "Tegan" overreached and shared an entire drive of information about the twins with a fan named Julie that the penny dropped. “I had become friends with Tegan and it had become a long-term friendship,” says Julie in the trailer. “At some point, she sent me a shared drive and a password. It felt off, so I reached out to her management and I got a text that says, ‘She has no idea who you are.’ And I said, ‘Well, then Tegan has a big problem.'”

As the extent of the deception was uncovered, the Quins were horrified to discover that the catfisher had stolen extremely personal information relating to the sisters, including scans of their passports, private photographs, and even their mother's medical records.

Says Tegan in the trailer, "It introduced the idea that it was someone we know coming after our friends, me, my girlfriend, and that just made me question everyone around me." The trailer then alludes to how the situation worsened but you'll have to watch the documentary for the rest. "Fake Tegan systematically destroyed my life,” sums up the real twin.

Fanatical: The Catfishing of Tegan and Sara is directed by Erin Lee Carr, whose previous work includes the Netflix doc Britney vs Spears, and drops on 18 October via Hulu in the US and Disney+ in Canada.