The stories presented as being factual, in addition to being "ripped from the headlines," were also described as being based on original research that writer Robert Tralins had conducted.
The writers would often base stories directly on newspaper articles.
The show is very popular in Germany, where it is known as "X-Factor". Due to the popularity, seasons 3 and 4 aired in Germany before they premiered in the USA. To celebrate the show's 20th anniversary, On November 4, 2018, the German adaption X-Factor: Das Unfassbare kehrt zurück (2018) was produced, which was hosted by Detlef Bothe. However, reception has been highly negative owing to the fact that amateur actors were cast and the episodes were produced cheaply.
Unlike other international versions of the show, in the German version the narrator between the cases was cut.