The Doctor’s strategic battle against the Cybermen’s doomsday device to prevent Earth’s annihilation

The Doctor devises a dangerous plan to exploit the androids' programmed duty to protect the hatch. Adric’s near-capture by the androids forces Scott to reveal their position as the Doctor …

Adric and the Doctor descend into the cavern to disable a bomb meant to irreversibly poison Earth’s atmosphere. The Doctor identifies the release mechanism and urges Adric to withdraw, but …

The Doctor scrambles to dismantle a cybernetic bomb before time runs out, ordering Adric to set the TARDIS coordinates to zero. He reveals the device can be disarmed through signal …