NOT A TRUE STORY!

As others have pointed out, movie makers use the gimmick of saying "Based on a True Story" to manipulate the viewers' emotions. "Glory Road" is one of may favorites. There really was an all black starting line-up that won the national championship but so many of the racist events portrayed in the movie, did not even happen (fight in the diner bathroom, trashed hotel rooms, racial slurs by the Seattle U. fans, Confed flag & "Dixie" at the Kentucky game, etc.).

When they take the "Based on a True Story" back a degree, it becomes "Based on True Events". You could stick that monicker on "Forest Gump".

This movie takes it back even further. It is "Inspired by Real Events". There have been FBI agents go undercover into radical groups. That is probably where similarity ends. And it isn't "Based" on anything. It's "Inspired" by something.

If Lewis Carroll saw a little girl chasing a rabbit, do you think he could say "Alice in Wonderland" was "Inspired by Real Events"?