Episode 1 Nick Cutter, Evolutionary Zoologist, finds himself confronted with the subject of his studies in a way he could never have imagined. Prompted by the enthusiasm of his graduate student Connor Temple, Cutter and lab technician Stephen Hart go to investigate strange animal sightings in the Forest of Dean. Close by, Abby Maitland, a zoo animal handler, is discovering the forest is home to a very strange pet. Could a lizard picked up by a young boy be an entirely new species? Claudia Brown, Civil Servant, hopes Cutter will dismiss the sightings. However, he's reluctant to oblige. There's more than professional intrigue behind his investigations; eight years ago his wife disappeared from the heart of the forest. Cutter invites Claudia to join the search, and they find a petrified Abby face to face with Scutosaurus - a giant beast from the Permian Era of 250 million years ago. Abby's convinced the Scutosaurus is "pure veggie", so what's behind the sickening sight of a dead cow hauled high into a tree? The young boy's tales of a monster at his window confirm Cutter's worst fears. A savage Gorgonopsid - one of the most dangerous predators of the Permian Era - is on the loose. Only Stephen's bravery manages to stop the boy and his teacher becoming its next meal. Where are these creatures coming from? The Scutosaurus leads the team to the answer: a shimmering in the air, a distortion in the light and suddenly the Scutosaurus disappears before them. A rip in time - an anomaly - that leads back to prehistoric times. Cutter is determined to make the trip through, convinced that the answer to his wife's disappearance could lie on the other side.
Episode 2 Cutter starts to suspect that Helen knew about the anomaly. While everyone presumes the discovery of her camera, millions of years in the past, confirms her death, Cutter is developing a different theory. But for now, he's keeping his speculations to himself. Lester is growing increasingly sceptical of Cutter, but Claudia's defends him as their only expert and Lester agrees to keep him involved... for now. Emotions run high, and Lester suspects Claudia has ulterior motives for keeping Cutter onboard. Meanwhile, Abby's hoping that Stephen might start to see her as more than just an ???animal expert'. Similarly, Connor tries to win Abby over with a night's camping, following up a top ???dinosaur-sighting' lead. His hopes for adventure fail dramatically, while creatures of the very real variety start to invade the London Underground. In the labyrinth of tunnels, SAS soldiers come under attack from giant spiders and are forced to retreat. But when Cutter and his team head down to investigate, they find something far more ferocious waiting for them: A huge, slithering, fifteen-foot beast, a vicious ancestor of the millipede - an Arthropleura. Stephen and Abby escape, but Cutter becomes lost in a maze of underground passages. Stephen returns Abby to safety and makes a desperate attempt to rescue his old friend from the fangs of Arthropleura but is attacked himself. Waiting to die, in his poison induced delirium, he thinks he sees Helen; and she has a message for Cutter.
Episode 3 Cutter is desperate to make Lester realise the seriousness of the situation, but he remains infuriatingly optimistic, hoping that this problem will disappear as quickly as it arrived. But he's not in luck. The arrival of a vicious sea creature, a Mosasaur, at a local pool is bad news for a pair of young lifeguards. The boy becomes the Mosasaur's next meal and the girl is charged with his murder. However, Cutter realises the truth when the boy's regurgitated body is found in a nearby reservoir; they've got a prehistoric killer in their waters. The anomaly has moved from the swimming pool to the depths of the reservoir. A diver is lost into the darkness of the anomaly, and another Mosasaur is unleashed and attacks Abby. Will Connor find the strength to protect her? And where will the anomaly move to next? Cutter thinks the anomaly is running along a kind of temporal fault line, but Lester is quick to dismiss his ideas. Meanwhile a young mother (who lives along the predicted line) is in the basement when she notices a small leak, which quickly turns into a flood. She sends a plumber down to investigate, but a creature from the Cretaceous is waiting, ready to pounce.
Episode 4 Helen Cutter, now in custody at the Home Office, is refusing to co-operate. She is the only one who understands how the anomalies work, but for now she's keeping her secrets safe. Besides, they have more pressing issues to deal with - a new anomaly has opened and Helen can show them where. If they're quick they might just be able to stop the next incursion. Claudia dislikes Helen, but puts her scepticism aside, giving Helen the chance to redeem herself. But instead of helping, Helen uses the anomaly to escape, leaving in her wake a flock of dodos! Contrary to reputation, these birds are far from harmless as Connor's suspicious friends discover. Connor's secret life, full of late night excursions, is really starting to bug Tom and Duncan. They set out on a mission to discover what's going on. They steal a dodo, unaware that it's carrying a deadly parasite. With one bite, Tom is infected. Can the others find him before a pandemic is unleashed? Tom finds himself struggling with an urge to attack people. A staunch conspiracy theorist, he seeks out Abby for answers. A frantic race ensues to find Abby before it's too late. Culminating as the dangerous reality of the anomalies hits Connor hard. Is he strong enough to go on?
Episode 5 Lester piles the pressure, but Cutter has no neat solutions for the enigma of the anomalies. Claudia is stuck in the middle, torn between her head and her heart. Meanwhile, Connor moves onto Abby's sofa, and is sure it's only a matter of time before she succumbs to his charms. Unfortunately, she still has her eye on Stephen, despite their proclamations of a platonic friendship. The discovery of a murdered golfer and an anomaly in the sky poses a whole host of new problems. Soon they spot their aerial killer. A huge Pteranodon, with a wingspan of forty feet, swoops straight for Connor. But as Special Forces aim to shoot, Cutter pushes the gun away, much to Claudia's frustration. The Pteranodon escapes and the truth is revealed. Rex, the prehistoric pet kept by Abby was with Connor, his presence attracted the Pteranodon, and he's now lost somewhere in the hotel grounds. Tensions between the group become strained. But thanks to Stephen, the Pteranodon is caught and tranquilized - but not before Claudia is knocked out by it's flailing wing. Waking up in the medical unit, Claudia is terrified to find she has temporarily lost her sight. Deep in the undergrowth, Abby and Connor, searching for Rex, come across a sinister sight. Surrounding a stripped carcass sit a pack of small, vicious Agnurognathus with razor sharp teeth. Scared for their lives, Abby and Connor are relieved when the Pterosaurs suddenly take off...
Episode 6 Helen returns claiming to know the reason behind a recent spate of disappearances - a dangerous predator is amongst them, claiming its victims for food. This beast is unlike any other, It is from the future. Tracking this highly intelligent animal pushes our team to its limits. At its lair they find a squirming nest of babies and the parent predator, desperate to protect its young, is close behind. A furious fight ensues. With the creature finally dead, Helen makes a plea to save the babies. She wants to use them to find the future anomaly. Their homing instincts could lead the way. Lester agrees - if they can locate the wormhole, then he can attempt to secure it. But first, the team must travel back to the Permian Era through the re-opened anomaly in the Forest of Dean. This is where the future predator came through and as Cutter soon discovers, its arrival was no accident. Cutter and Helen's journey into the past is full of danger and treachery. The remaining parent of the screeching babies has suddenly appeared and is upon them. But this beast has clearly never encountered an ancient Gorgonopsid before. As the most powerful creatures from past and future battle it out, our team escape back into the present. But the surprises don't end there. Helen has one final blow to deliver. She's returning to prehistoric times but this time, she doesn't want to go it alone. Secrets from the past are exposed in an explosive showdown.