Range and Norna’s partnership strained between scientific duty and familial loyalty as they pursue the truth about Frontios’ disappearances amid escalating disaster and deception.

Tegan defies Norna’s warnings and refuses to abandon the Doctor, insisting on returning to the treacherous tunnels. When Range learns of her plan, he initially hesitates but ultimately disregards her …

Range and Norna stumble upon a long-lost map belonging to Captain Revere, its markings hinting at a deeper knowledge of the treacherous cave system on Frontios. Their discovery shifts focus …