Codal's psychological struggle between survival instincts and moral imperative to protect others during escalating crises on Spiridon.

Trapped in the cramped tunnels beneath the planet’s surface, the Doctor faces a relentless energy-releasing metal snake while pursued by Daleks above. Using quick thinking, he maneuvers the creature into …

The Doctor and Sarah closely examine ancient markings Bellal has carved into the tunnel wall, recognizing them as identical to symbols found in an Earth temple. This sparks a revelation …