When a nuclear submarine encounters an anomaly and Liopleurodon in the sea, the team are called aboard to help. They soon find themselves under attack and get sucked back through an anomaly, with Liopleurodons damaging the outside of the sub. The team must not only capture the panicked Eustreptospondylus aboard, but fix the sub exterior in order to get home.

Cast: Ruth Bradley, Jonathan Byrne, Ruth Kearney, Ben Mansfield, Ciarán McMenamin, Ben Miller, Andrew Lee Potts, Hannah Spearritt