A trawler is torn to pieces by a mysterious creature off the Irish coast; meanwhile Connor's anomaly detector goes off the charts. Half a dozen anomalies have appeared, all on one deserted — yet politically contentious — island.
The team battles through a deadly storm to reach the island, only to find themselves powerless against the great creatures roaming free across the landscape. In fear of their lives they seek refuge inside a sunlit anomaly — watching helplessly as it closes behind them, marooning them in the past. Back in the present Lester and Jenny must fight to control an escalating political catastrophe as the British, Irish and French governments all struggle to take control of the island.
In the North Atlantic a fishing trawler named the Cormorant is struggling through a storm when it is suddenly attacked by an unknown creature. Meanwhile Connor is upgrading the anomaly detector to improve its accuracy despite Cutter's worries. While demonstrating it detects half a dozen anomalies on and around Guns Island, a former British-controlled island and now being fought over by France and Ireland. Hoping that the situation is contained on the island, and due to the water being cooler than most prehistoric eras, Lester decides to send the team to deal with potential creatures. Cutter believes that because the creatures may end up going through the wrong anomaly later, that they will need to kill them on this one occasion, prompting Lester to attach a team of soldiers led by Captain Willoby. Jenny escorts the team's weapons to Cork in a diplomatic bag courtesy of a favour owed to Lester, but due to the harsh winds the team is forced to take another trawler, the Polar Star, instead of a helicopter. Jenny tells Cutter that the anomalies have closed but new ones have opened in their place, and worries that she may have aroused suspicions with the weapons.
En-route to the island, Stephen spots a Liopleurodon in the water, but due to the cold temperatures it doesn't bother them and Cutter suspects it is what attacked the Cormorant. After a rough landing in which they lose half of their equipment and a treacherous climb, both of which take a toll on Abby, the team makes it to the plateau. Meanwhile Jenny is released from Irish Special Branch custody by Lester, who then sends her to join the Irish military who are on their way to Guns Island. Lester admits that their potential cover story of the island being a chemical facility when the British had the island was in fact true, and has ordered Willoby to check that the island base is still secure. Connor wakes up to find an injured Iguanodon, which Cutter puts out of its misery. The Irish send a helicopter up to the island with Jenny among them, but due to the winds it crashes, killing the co-pilot. The team see this and rescues the survivors, and take them to their base camp, wary of a pair of Eotyrannus nearby.
Later Cutter calls Lester with a satellite phone, berating him for sending Jenny and requesting more supplies and an evac for the injured pilot Brice. As the eye of the storm passes over the island, Connor notices there are no anomalies open now and theorises the storm and the island's geology affect the anomalies. The team decides to make their way to the island bunker for better shelter, but along the way the pack of Eotyrannus attacks, resulting in the deaths of Farnsworth and Watts while the others secure themselves in the bunker. When the storm returns, so do the anomalies. Willoby ensures the former chemical base is no risk, but refuses to allow Cutter and Connor to confirm an anomaly within a secured park of the base. Later the Eotyrannus return again, and Stephen is crushed while Bristow is killed. Trapped inside, Cutter convinces Willoby to allow him into the secured location with the anomaly, hoping they can use it to escape. After checking the area is safe, Cutter brings the team into the Early Cretaceous and they begin searching for another anomaly that will lead back to Guns Island.
Lester meanwhile has been ordered by his superiors to accompany a French frigate heading to the island, and reluctantly tells the captain about the anomalies, wanting to be with the first team to go onto the island. In the Cretaceous, the team is forced to move their camp when a trio of Neovenator hunt the nearby herd of Iguanodon. Connor is unable to detect any new anomalies, and during the night Stephen starts to succumb to his injuries, and apologises to Cutter about his affair with Helen. Desperate, Connor, Willoby and McCann go out to see if they can find an anomaly. They succeed, and McCann asserts they should save themselves and runs for the anomaly, but is brought down by a pack of Dromaeosaurs. The French team arrives on the island with Lester, and find the base empty, and Lester realises they have gone through. He takes a rifle and flares from a soldier and randomly picks an anomaly to go through.
The team makes their way to the anomaly in the rain, and as it starts to flood they are attacked by the Dromaeosaurs. Brice is killed, and Jenny spots one of Lester's flares, and the team rush toward him. Willoby covers them but is also killed. As the team rush through the anomaly as it and the rest close. Later Stephen is airlifted out while Lester confirms Cutter's suspicions that the bunker was built around the anomaly fifty years earlier so that it could be studied before it closed, but wasn't allowed to tell him.
- Abby Maitland
- Connor Temple
- Nick Cutter
- James Lester
- Jenny Lewis
- Stephen Hart
- Claudia Brown (mentioned)
- Captain John Willoby (only appearance)
- Sergeant Callum Fox
- Corporal Peter Farnsworth (only appearance)
- Lance Corporal Anita Watts (only appearance)
- Private David Doody
- Private Joe Bristow (only appearance)
- Liopleurodon (first appearance)
- Iguanodon (only appearance)
- Eotyrannus (only appearance)
- Unidentified sauropods
- Badger-Like Mammal (only appearance)
- Neovenator (only appearance)
- Polacanthus (only appearance)
- Unidentified Dromaeosaur
- Raptors (mentioned)
- Atlantic Ocean
- Anomaly Research Centre
- Cork (only appearance)
- Guns Island (only appearance)
- France (only appearance)
- Castle Cross Shopping Mall (mentioned)
On the original cover:
- It was released in hardback and softback.
- The Liopleurodon was represented by a Mosasaur using a promotional picture from Episode 1.3, as the Mosasaur was the closest thing in the television series to a Liopleurodon.
On the re-release:
- It was only released in softback.
- When this novel was re-released in Softback, the cover was altered, Stephen was replaced by Connor, likely to appeal to new fans joining at Series 4. However it is not accurate as Connor has his hair cut here in the style he had it in Series 3, and this book takes place during Series 2, meaning he didn't have his hair like this at that time.
- This is the first time Abby and Connor go through an Anomaly and the only time for Jenny and Lester.
- Connor refers to the events of Episode 2.1.
- Oliver Leek did not appear and was not mentioned for unknown reasons.
- Stephen and Nick talk as if the latter's affair with Helen occured recently but it actually happened over 8 years ago.
- Both Cutter and Connor mention the Raptor incursion at the Shopping mall in Episode 2.1.
- Lester mentioned the Peru Anomaly incursion in the Shadow of the Jaguar.