Connor and Abby join forces to investigate another anomaly suspected of being in the New Forest (Hampshire/Dorset). Meanwhile gigantic bugs (beetles? spiders? ancient...) attack people on the London Underground and Professor Cutter concludes that another anomaly has opened up, to a much earlier prehistoric era --- the carboniferous. After a special forces sortie, he is persuaded to allow Abby to join the team as they go to see for themselves after Lester has agreed (under protest) to stop trains through the affected tunnel section.