During the recap from the previous episode, the Sensorite does not touch the spaceship's window, as it did during the original cliffhanger.
During the recap from the previous episode, the Sensorite alien design outside the spaceship's window, does not match the design from the original cliffhanger.
Carol's hairstyle is slightly different from the previous episode, despite no time having elapsed.
When Ian and Barbara walk along a corridor on the spaceship, one of the walls visibly wobbles.
About a third of the way in, the left ear of the Sensorite actor who is communicating with the First Elder is visible.
The Doctor suggests that the melting point of iron is 1539 degrees centigrade, which is one degree above the actual melting point. He then suggests that the melting point of molybdenum is 2622 degrees centigrade, which is one degree below the actual melting point.