Threshold

Threshold was produced by Brannon Braga, David S. Goyer and David Heyman, and was designed from the start as a serialized show rather than an episodic, closed-ended series.

Producer David S. Goyer revealed that the show was planned as a three-year arc that would have changed its title each season: from 'Threshold' (contact) to 'Foothold' (aliens gaining a foothold) to 'Stranglehold' (aliens overthrowing humanity and becoming overlords).

Word that the series was being cancelled arrived midway through the shooting of the episode 'Alienville', prompting the crew to rewrite the ending to show Molly having a dream conversation with an alien-human baby who appears as a nine-year-old boy foretelling her eventual death.

CBS moved Threshold from Friday to Tuesday nights hoping to boost ratings, but this backfired: the show suffered a sharp ratings drop on its first Tuesday broadcast because it competed directly with the popular Law & Order: Special Victims Unit and, on one occasion, the American Music Awards, leading to its cancellation the very next day.

Because of the cancellation, four completed episodes were never broadcast on CBS in the United States; they were instead first aired in the UK on Sky1, the channel that co-produced the series, and were later included on the DVD release.

Threshold was the first CBS television series to use streaming video to re-air new episodes after their original broadcast, posting each episode on the CBS website five days after airing and keeping it available for three days, a concept CBS later expanded into its 'Innertube' streaming platform.

Catherine Bell was announced to join the cast as botanist Dr. Daphne Larson shortly before the show's cancellation, but she only appeared in the unaired episode 'Outbreak' and was merely referenced by name afterward, never appearing again before the series ended.

In several international markets the series was retitled, airing in Germany as 'Nemesis: Der Angriff' on ProSieben and in Quebec as 'Threshold: premier contact' on Ztélé.