ChicagoEpguides reported that at 0:22:42 the voiceover from Howard da Silva at the beginning of episode 2 is mistakenly retained ("The signal from the missing ship grows stronger as the crew plummets to the underworld.")

Intro: The ancient Greek world for 'underworld' was 'hades.' It was the resting place of the dead. In modern art, 'underworld' refers to the criminial element of our society. The title of tonight's Doctor Who adventure is more literal. But this underworld has a Greek element as well: the oracle. Journey with us now to the edge of creation and "Underworld."

Outro: Next week, The Doctor returns to his home planet of Gallifrey to be inducted as president of the Time Lords and to be connected to The Matrix, the sum total of all Time Lord knowledge and experience. Tune in. You may learn something yourself as you experience "The Invasion of Time." [source: ChicagoEpguides]