Philip and Connor secretly open an anomaly within the ARC, which connects to a time far in the future. Philip is excited; this is providing them with the best anomaly data yet, and even better, they created it themselves. But Matt is worried – an anomaly should be locked. Philip strongly refuses, and even posts a guard at the lab to prevent the team from interfering.

Matt expresses his concerns to Abby, who asks him to give her some time to try to persuade Connor to stop before Matt destroys the machine. As she does so, the guard is overwhelmed by vicious beetles that strip him to the bone.

Very soon the swarm of beetles is taking over Connor's lab, chewing through everything in sight. The ARC bio-scan soon kicks the building into lockdown, isolating the creatures and Matt realises the beetles will suffocate inside the room. But before long, the creatures are chewing through the wall and into the air ducts, quickly swarming through the building.

While the others track down the beetles through the ducts, Matt sees his chance and destroys Connor's machine while he can.

The team work out a way to stop the creatures, using their queen to lure them into the Ops area and pesticides to take them down. However, in the operation Jess is bitten by a beetle and goes into anaphylactic shock. In his anger, Becker shoots at the queen, killing her and losing control of the swarm. The ARC quickly becomes overrun with the creatures, which are spreading throughout the building. As the outer boundaries of the ARC become threatened and Prospero Industries - the scientific company that owns about half of the ARC - comes under scrutiny, Philip has a solution but it will destroy the ARC, taking the team with it.

As Becker, Abby, and Emily attempt to find a way to treat Jess, Connor has an idea to try to redeem himself and his actions: he can harness the power of this future anomaly to create a shockwave that will wipe out the beetles. The problem is, Matt has destroyed the machine. It seems all is lost, until Matt produces from his pocket a hard drive containing the data that Abby downloaded from Connor's machine. With time running out, the pair fix the machine and fight their way back through the beetles to join the others in the menagerie. We see the building rock as the pulse created by the closing anomaly echoes through the ARC, shaking it to its very foundations . . .

Battered and bruised, the team emerge from the room, having defeated the creatures and closed the anomaly in one go. But as the massive ARC clean-up begins, Connor is beginning to doubt Philip's motivations. Does he really have the best interests of the ARC at heart?

This creature will be bigger and meaner than the one that exists now. They are coming through the anomaly from the future and have evolved into something that can withstand the hostile environment that the Earth's surface has become.

The Devil's Coach Horse beetle, which is part of the same family, raises its long and uncovered abdomen and opens its jaws, rather like a scorpion, when threatened. Although it has no 'sting in its tail' it can give a painful bite with its strong pincer-like jaws. It also emits a foul-smelling odour as a defensive secretion from a pair of white glands at the end of its abdomen.

A regular anomaly alert turns sour when the team realise they've accidentally returned a raptor through to the wrong time. With the sense of responsibility weighing on their shoulders, Matt returns through the anomaly, asking Abby to find out what Connor's been up to in his lab. He thinks it's got something to do with whatever Philip's been planning. Abby is reluctant to betray Connor's trust but shares Matt's concerns about what Connor is up to.

Realising the raptor is responsible for a number of gruesome murders, Matt soon manages to track down the creature to a fruit warehouse. He's about to take it down when a mysterious cloaked figure distracts him and leads him straight into the path of a raptor attack. The hood falls . . . Emily is back. Just as they struggle to come to terms with seeing each other again, two dark strangers grab Emily from behind and drag her away, leaving Matt unconscious…

Meanwhile, back at the ARC, Abby knows she has to try to reconnect with Connor, as they've been spending too much time apart. However, a nasty encounter with April on her way to his lab makes her wonder if Matt is right – Connor is up to something in his lab that she isn't meant to know about. Before, she was completely against it, but now she's more convinced than ever that she needs to know the truth and hatches a plan to infiltrate Connor's lab…

Emily is attempting to escape from her captors, who are revealed to be her husband and a doctor from the Bethlem hospital - her absence and "strange" behaviour have led to her husband having her sectioned. Just as it seems that all is lost the raptor returns, attacking their coach, killing the doctor, and allowing Emily to escape back to Matt and the warehouse - but not before a passer-by notices the carnage and blames Emily for it. Mob mentality ensues as Matt and Emily become trapped in the warehouse with a raptor on the loose.

With the mob building in numbers outside, Matt and Emily struggle to get control of the raptor. Having found and stunned the creature, the only option is for Matt and Emily to take it back through the anomaly. Emily takes some persuading - Matt's time isn't where she belongs. But as he points out, here, they think she's a murderer. Just as it looks like she's made a decision, her husband reappears, brandishing a pistol. Distracting him, they make a quick escape through the anomaly with the raptor.

Abby is hiding out in Connor's lab, downloading his data to a portable hard drive. But little does she know that a suspicious April in stalking around, looking for her. Just in time, she manages to finish before April can stumble across her.

Returning to 2011, Emily has to think hard about her future – return home to 1868 as an accused murderer or stay out of time with Matt. But there's little time to argue as her husband bursts through the anomaly, shooting at the team. Eventually capturing and disarming him, it looks like he'll go back through the anomaly willingly, but he has other plans – grabbing Emily as he attempts to go through… Things look bleak until the raptor, freshly conscious, attacks and kills him. With nothing left to go back for, Emily decides to stay in the present.

Returning to the ARC, Abby and Connor are once again at odds – April has persuaded Connor that Abby is up to something and Connor can't help but wonder. Even news of Philip's involvement with Helen does nothing to persuade him that Abby is on his side. Feeling further apart than ever, Abby decides she has just one option and heads to Matt's lab to hand over the hard drive.

Meanwhile, working late in his lab, Connor has had a breakthrough that could change everything – and Philip is the first person he calls . . .

"Raptors" as a word was popularised by Jurassic Park and is slightly frowned upon by palaeontologists. It is a generic term to describe a group of agile dinosaur predators called the dromaeosaurids. This group were distinguished by their lightweight skeletons, long arms, and the lethal sickle-shaped claw on their second toe. Although as a group they evolved in the Jurassic period, they thrived throughout the Cretaceous.

When a nuclear submarine encounters an anomaly and liopleurodon in the sea the team are called aboard to help. After a briefing they board the sub, where they discover a creature resembling a raptor ancestor that has been brought on board by the crew. While Abby examines the creature, Connor plans a way to lock the anomaly, utilising the sub's torpedo system to blast it closed. All seems to be going to plan, until the sub is rocked by a massive bang.

The sub is under attack by liopleurodon, knocking out the captain and leaving just one officer and the team to sail the sub to safety. The sub is sucked through the anomaly, knocking out the electrics.

Meanwhile, at the ARC Lester has to cope with the intervention of navy bigwigs, threatening to nuke the sub if the team can't fix the problem. The political fallout from any damage caused by the anomaly is too big to ignore. Jess and Lester are working against the clock as they attempt to distract the admiral long enough for the team to do their stuff.

While Connor heads off to fix the electrics Matt and Abby head out onto a mini-sub in an attempt to repair the external damage. But the constant threat of the liopleurodon is making their task even more difficult. Meanwhile, the freshly-woken raptor ancestor is stalking the corridors of the sub, having already taken out another guard.

Connor is still attempting to fix the internal damage when the creature attacks him. He struggles to fight back as he protects the ship from further damage. Matt and Abby turn up in the nick of time but not before a headlong collision between sub and liopleurodon allows the creature to escape and creates a massive leak, putting the team in further danger.

Racing against the clock (and the leak) Connor and Abby eventually manage to take the creature down with a combination of wet floors and an EMD bolt. Then Matt has a brainwave – perhaps they can use the torpedo to kill two birds with one stone – forcing the creature out of the sub and closing the anomaly in the process. Transferring it to the torpedo bay, Matt plans to flood the room and eject the creature as a distraction for the liopleurodon, allowing them to escape. Little do they know, though, that Lester is doing all he can to stop the admiral firing a nuclear torpedo straight at them . . .