Shadow of the Jaguar starts in the Peruvian rainforest, where Cam and Jaime Bairstow, the sons of a British aristocrat, are out in a biological reserve. They go out at night to relieve themselves but Jaime is killed by an unseen predator and Cam is severely wounded. James Lester is summoned to the house of Sir Charles Bairstow, father of Cam and Jaime, and asks James whether his team could head out and recover the boys. Lester refuses, but later that morning, when the rest of the team arrive at the Anomaly Research Centre, Sir Charles calls and this time has sent a demand that they go. Lester reluctantly accedes, and while some of the team (Connor particularly) find the entire thing very exciting, the rest of the team are very concerned about the prospect of overseas anomalies. Also, Cutter receives a message from an old student of his working in the reserve, who finds that the endangered species resident are fleeing, and the student has also noted inexplicable tracks and bones. Cutter, Stephen, Connor, Abby and Jenny fly off to Peru.
When they arrive they discover that a pack of unknown animals have been killing local villagers, and as the team attempt to track down the animals, they discover the presence of vicious Thylacosmilus. The prehistoric creatures are also known to local poachers, who see the creatures as an investment to their business and will do anything to protect it. Even worse, the team discover the Thylacosmilus aren't killing at random, but are in thrall to a more sinister, and far more dangerous predator from the future. Meanwhile Jenny was kidnapped,however later she was rescued by Stark, an SAS soldier assigned to the team as security escort on the team. The team find the anomaly in a temple built for Incan god Pacha Kamaq, attracted by the pheromones they follow the five remaining Thylacosmilus. One man that part of the research team, Sean Lucas, manages to shoot two and stun one, but suddenly, a Future Bird comes through, killing Lucas but Cutter, Stephen, Abby, Connor, Nando, and the guide stay alive. Cutter attacks it with a flame gun that Lucas had on him before being killed by the bird. Cutter uses the flame gun to drive the remaining Thylascomilus and Future Bird through the Anomaly.
- Nick Cutter
- Stephen Hart
- Connor Temple
- Abby Maitland
- Jenny Lewis
- James Lester
- Sean Lucas
- Cam Bairstow
- Jaime Bairstow
- Sir Charles Bairstow
- Nando Estevez
- Esteban Estevez
- Jake Stark
On the original cover:
- Was released in hardback and softback.
- The Thylacosmilus was represented by a Smilodon using a promotional picture from Episode 2.3, as the Smilodon was the closest thing in the television series to a Thylacosmilus.
- Nick Cutter's image was taken from Episode 2.2.
- One of the covers had a theropod dinosaur on it, despite there being not dinosaurs in the book.
On the re-release:
- It was only released in softback.
- Cutter was replaced by Abby, likely to appeal to new fans joining at Series 4. However it is not accurate as Abby has her hair cut here in the style she had it in Series 3, and this book takes place during Series 2, meaning she didn't have her hair like this at that time.
- This is the shortest book of all the novels.
- A label on the Matrix in Series 3 labels Pacha Kamaq/Future Bird, proving that the novel is canon.
- Oliver Leek did not appear and was not mentioned for unknown reasons.
- The Virgin Mary and Jesus are mentioned in this book, confirming that Christianity, as a religion, exists in the Primeval universe.
- El Chupacabra is mentioned numerous times in this book, confirming that reports of this particular cryptid exist in the Primeval universe.