In Cretaceous Texas, Drew stood in the blind end, explaining his plan to Cynthia and Leon. "For this, I'm going to use myself as bait. I'm going to run out onto the lake and attract them to shore, before running out of the water and towards the stockade; I can easily outrun a Deinosuchus, When I get to the blind end, you guys set up the portal and send them back to the park. Any questions?". Leon raised his hand and said, "Aside from pointing out how utterly reckless and death-defying this particular stunt is…" Drew waved him off, "Duly noted and ignored."

Drew walked out onto the lake and waded until he was hip-deep in the water. Then he began hitting the surface of the water with the paddle, hoping that the vibrations would attract the Deinosuchus. After a few minutes, he was proven right when a group Deinosuchus began swimming towards him. As they got closer he moved further and further back, before he ran out on to land, towards the stockade, with the Deinosuchus in hot pursuit. As they entered the stockade, they turned to single file, with Drew managing to keep one step ahead of them. When he reached the blind end, Drew yelled at Cynthia and Leon, "Set up the portal!" As Drew ran through the posts at the blind end, the two scrambled to the end of the stockade, pressed the button and the portal whirred into life. The first Deinosuchus, not even changing its path, walked through the portal, into the present, as did the next and the next one after it. Drew sighed in relief; this was easier than he thought it would have been.

However, the last Deinosuchus veered slightly to the left, breaking two of the posts at the stockade's blind end. Drew's eyes widened in horror; if it managed to break through the posts, it would attack them. Drew indicated that Cynthia turn off the portal and ran over to the posts, grabbing them and trying to keep them upright; Leon ran over to join him. The Deinosuchus continued to snap and hiss in frustration as Drew and Leon attempted to keep the panels upright. Whilst this was happening, Drew gestured to Cynthia to get to the Jeep; attaching the three poles at the end of the stockade to the Jeep, she revved up the engine and pulled away the three poles. Drew and Leon dived out of the way as the Deinosuchus charged through the gap. Drew pointed the portal remote in its direction and the portal whirred into life; not changing its trajectory, the Deinosuchus went through, into the present. Drew turned to his team and smiled, "Job done. Let's get back to the park." After packing everything up, they drove through the Jeep, into the portal…

The first thing they heard when they left the portal were the shouts of their colleagues; however, these weren't shouts of joy, but rather fear. Everyone was panicking. Confused, the team looked at each other. Drew walked up to Will and asked, "What's going on?" Will turned to him and practically screamed, "Something big's just happened! A Tarbosaurus has escaped!" The calmer Nikolai took over the conversation, "About forty minutes ago, we received a communication Drew looked at them both and said, "I'll go and find it." Leon suddenly interjected, "I'm coming with you. You might need help." Drew gave him a puzzled look, "What do you mean, 'help'?" Ignoring him, Leon looked purposefully at Nikolai, "First we need to stop off at Theropod Kingdom. I need to get a few things." Nikolai looked at him; he knew what Leon meant. "Alright, here's where the Tarbosaurus was last seen…"

A few minutes later, Drew and Leon were sitting in a park Jeep, with three park containment trucks, each containing an allosaur behind him. As he walked around, he explained his plan to Drew, "This is a basic scent drill. We've done this a billion times, only this time the lure's a little bit bigger. When they find it – and they will find it – they're going to herd it back to its paddock." Drew clapped his hands, "Sorted." Leon jumped out of the Park jeep in front of the containment trucks, carrying a towel enriched with Tarbosaurus scent. He walked down the line, offering the scent to Drogon, Rhaegal and Viserion, who sniffed eagerly. In their crates, they began to buck and screech, eager to find the source of the smell. Once he was done, Leon got in the Jeep with Drew, who revved the engine.

Nikolai, Kyle, Jack and Collete were sitting in the control room, watching all this happen. Nikolai said, "Incredible. This might actually work", whilst Jack said to Collete, "You didn't really believe it, did you? When he said he was going to do this? Well, here he is."

Leon held his hand up to signal to the keepers driving the trucks; all the keepers put their fingers on the buttons that would release the allosaurs. Leon lowered his hand and the keepers pressed the buttons, opening the trucks.

The Allosaurus burst out, searching for their target, with Drew and Leon following in the Jeep.

In the Jeep, Drew and Leon sped up, joining the three running allosaurs, a pack on the hunt. They reached a clearing in the forest, and the allosaurs slowed down, lowering their heads to the ground. Drew turned to Leon quietly, "They've found something." Leon nodded, "I know." Standing in the clearing, about 200 metres away, was the unmistakeable form of the Tarbosaurus.

Leon whistled quietly to Drogon, Rhaegal and Viserion, who tensed, awaiting the order from their alpha. Leon raised his hand, making sure that all three of the theropods could see him, and lowered it, before saying "Get it". The Tarbosaurus only had time for a single growl of outrage as the Allosaurus ran into the clearing, splitting up and running in a circle around the larger theropod, blocking off its retreat.

The Allosaurus had the larger theropod surrounded. Suddenly, the Tarbosaurus lashed out at Viserion, who nimbly jumped back and dodged its blows. Whilst the larger theropod was distracted, Rhaegal darted out and snapped at its feet. They repeated this process for half an hour; every time they did it, the Tarbosaurus moved a little further forward, out of the clearing. The Tarbosaurus growled in indignation, and ran off. The Allosaurus followed it, snapping at its heels like sheepdogs. Every time the Tarbosaurus attempted to move in a certain direction, the allosaurs would block its path, steering it out of the clearing. Drew and Leon went on ahead in the Jeep, with Leon giving cues to Drogon, Rhaegal and Viserion.

After about an hour, the chase had taken them to the gate of the Tarbosaurus paddock at Theropod Kingdom. Leon raised his hand and said, "Leave", to which the allosaurs backed off from their target, and nodded to the keepers standing on the walkway above the paddock, who dropped a large chunk of meat in the paddock. The Tarbosaurus, having smelt the meat, dived through the open paddock door; once the Tarbosaurus entered the paddock, the door closed fully. Leon let out a sigh of relief, raised his communicator and said, "Nikolai? The Code Red is officially stood down." Nikolai, Kyle, Jack and Collete, watching from the control room, sighed in relief.

With that done, it was time to get the animals to their new homes.

Soon, all the Cretaceous Texas creatures had been transferred to their new homes. The Troodons had been moved to a paddock in Raptor Territory and were currently napping in the shade of a large tree, waiting for food to arrive. The Albertosaurus pack had been moved into a large paddock in Theropod Kingdom and were currently roaming their territory, waiting for their next meal. Meanwhile, the Deinosuchus were being kept in Mesozoic Tropics, in a river next to the Sarcosuchus; the two floats of giant crocodiles were currently engaged in a contest to out-roar each other.

The Nyctosaurus had been transferred to a new aviary in the pterosaur section, themed after a Cretaceous coastline. They were now flying around, exploring their new home. And the Parasaurolophus had been transferred to Mesozoic Safaris to join the eclectic mix of herbivores there. The herd had been transported in the park's large containment trucks.

Leon, meanwhile, was enjoying the fact that everyone now had faith in his allosaur training programme. Even the most sceptical people had been won over by the Tarbosaurus incident. Leon smiled; he felt proud that it had been a success. Not because of any boost to his ego (although there was a bit of that), but that he knew that the park was safe for the future. If a mass containment failure occurred, and some giant carnivore ended up running riot, these could stop it.

Next time on Prehistoric Earth

The team go back to Cretaceous Kansas

(A large, penguin-like bird hisses at Adrian)

On their most perilous mission yet

(A giant mosasaur grabs a shark)

To save the deadliest marine predators ever

(A group of mosasaurs surround Drew)

All next time on Prehistoric Earth: The Wavering Gulfs!

Animals rescued:

Albertosaurus sarchophagus: 5 (2 males, 3 females)

Deinosuchus riograndensis (3 males, 2 females)

Nyctosaurus gracilis: 5 (3 males, 2 females)

Parasaurolophus tubicen: 39 (15 males, 24 females)

Troodon formosus: 4 (2 males, 2 females)

However…

In a secluded part of the park, Cynthia lifted her communicator to her ear and said, "I'm here, boss." The person on the other end of the line said something, to which she responded, "Status update; nobody's found me out yet. And there's been quite a few… "new developments" since our last contact." She sighed, "Leon has been training three of the Allosaurus for quite some time now. They had their 'first mission' today, when a Tarbosaurus 'escaped'; the allosaurs succeeded in recapturing it." There was a pause, and Cynthia nodded, as the person on the other end said something. She responded with, "Oh, I wouldn't worry; this incident might have been a fluke." At this, she paused. "Might have been. However, I'll keep an eye on the situation; it could cause us some real problems in the future."

Cynthia sighed, before continuing, "In other news, we had a safety audit, which, despite an incident with the Borealosaurus, we managed to pass. Which reminds me… Remember the Jack Denham I was telling you about? Somewhat disappointingly, he's not who we were expecting him to be, so we can forget about that…" At this statement, Cynthia paused, to allow the person on the other end to speak, before speaking again, "Yes, I know. Continue my infiltration until further instructions and make sure I don't get compromised in that period. After all… you're the boss." She put down the communicator and walked out.