The Doctor and Jo head to Stangmoor Prison to investigate the Keller Machine, which drains the evil impulses from prisoners minds.

Following the destruction of the colour recordings Mind of Evil became the missing serial of the Jon Pertwee era, in that not even a frame survived in colour on a broadcast quality medium. But then came along Chroma Dot Recovery, or Colour Recovery as it as is called, a process so fantastic even the Doctor might call it magic. As fans know, many Jon Pertwee episodes only exist as black and white film recordings of colour videotape. What some clever boffins realized though, is that these black and white film recordings still contained the field information for the chroma (colour) signal as a series of dots. They have now figured out how transform those dots into an actual colour signal. The results are remarkable. And as of March 1st the colour restoration work undertaken on The Mind of Evil is complete.

Admission is free but you must book in advance, only 70 seats available.