Worried about the Old Silurian's growing friendship with the Doctor, the Young Silurian has the scientist infect Baker with a virus and then release him.
Did You Know?
The color master tape of this episode was wiped by the BBC in the 1970s and the BBC only held a 16mm black and white telerecording. The episode remained only in black in white until the 1990s, when the color signal from a domestic NTSC recording and the black and white telerecording were used to create a new color master on D3 digital tape. See more
As the Doctor warns UNIT about Major Baker's infection, a boom microphone shadow is visible next to Major Baker's head. See more
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