• A Rip in Time
• Dangerous Dimension
• The Lost Predator
• Fight for Survival

• Shadow of the Jaguar
• The Lost Island
• The Extinction Event
• Fire and Water

Created by Adrian Hodges, Primeval debuted in a blaze of publicity in February 2007, the first sci-fi series to have been broadcast on ITV1 in a number of years, and the first in even longer to have been given a Saturday evening slot — helped in no small part by the success of Doctor Who on BBC One which proved that family audiences do still exist.

Initially promoted as a "dinosaurs and time travel" drama, the series quickly laid out its stall by revealing that various prehistoric creatures (not just dinosaurs) were coming through mysterious anomalies into the present day and causing havoc wherever they appeared.

Enter Professor Nick Cutter (Douglas Henshall) — swiftly called in by Home Office official James Lester (Ben Miller) — who put his expertise in all things prehistoric to good use and assembled a team capable of tracking down and capturing/returning the various creatures. Along the way it was revealed that Cutter's wife had disappeared in the Forest of Dean some years previously, with the anomalies as good an explanation for her disappearance as any. As events would show, not only was Helen Cutter (Juliet Aubrey) still alive and well, but following her own agenda with regard to the anomalies and the creatures on the other side of them.

The other main characters in Season 1 were: Cutter's assistant Stephen Hart (James Murray); zoologist Abby Maitland (played by ex S-Club 7 star Hannah Spearrit); and Connor Temple (Andrew-Lee Potts), Cutter's enthusiastic, socially inept and ultra-geeky student. Also along for the ride was Claudia Brown (Lucy Brown), a colleague of Lester's.

Season 1 concluded with the first appearance of a creature from the future. The same episode also saw the timeline being changed and Claudia erased from history. But, as Season 2 was to demonstrate, in a show that involves changes to the timeline, you can always have the characters re-appearing under a different name and played by the same actress. Enter Jenny Lewis!

As well as featuring standalone stories, Season 2 also started to increasing focus on a story arc, with the team up against a conspiracy intent on using the creatures for their own ends. The storyline came to a head in the final episode of the season, in which Stephen met a grisly end — the only casualty thus far from the central team of characters.

Season 3 began broadcasting in late March 2009, and in its first episode introduced two new characters: Sarah Page (Laila Rouass), an Egyptologist intitially seen working for the British Museum, and Captain Becker (Ben Mansfield), the new head of security at the ARC. The following episode saw the first appearance of policeman Danny Quinn, played by Jason Flemyng. Needless to say, the influx of new characters was just a prelude to the departure of several familiar faces over the new few weeks later, as first Nick Cutter was murdered by his wife, Helen, and then Jenny left.

As befits a show that draws a regular audience, ITV delayed the transmission of the final episode by a week in order to show the final of Britain's Got Talent — in the process enabling disgruntled viewers to buy the complete season on DVD before it had even finished on ITV1. To add insult to injury, the final episode ended with Abby and Connor stranded up a tree, and Danny trapped in the past with no apparent hope of escaping home. Unsurprisingly, ITV swiftly announced that the series was too expensive to make and cancelled the series...

However, that wasn't to be the end of the series, as it was unexpectedly announced in September 2009 that a deal had been struck for a further thirteen episodes to be produced, split over two seasons. With BBC Worldwide stepping in to co-finance the series, Season 4 will debut on ITV1 in early 2011 with repeats later appearing on the Watch subscription channel. Season 5 will then be shown on Watch later the same year before it gets a repeat screening on ITV1.