EPISODE: The Mind of Evil: Episode Two
OVERALL EPISODE NUMBER: 284
STORY NUMBER: 056
TRANSMITTED: 06 February 1971
WRITER: Don Houghton
DIRECTOR: Timothy Combe
SCRIPT EDITOR: Terrance Dicks
PRODUCER: Barry Letts
FORMAT: VHS: Doctor Who - The Mind of Evil [VHS] 
Episode Format: 16mm b&w film recording
The Doctor is saved by Jo Grant who enters the room breaking the machine's hold over him. Benton is following Chin-Lee in the street but collapses as she taps into the power of the Keller Machine. The Doctor is called back to London by the Brigadier but Jo remains behind where she befriends the recovering & changed Barnham. Meanwhile Unit, in addition to guarding the conference, is now responsible for the transportation and disposal of a Thunderbolt Nerve as missile. However their phone communications are being monitored by a phone engineer working opposite......the Master in disguise! The Doctor & Brigadier meet with the new Chinese delegate who the Doctor befriends by speaking his own language. The Master meets with Chin-Lee and instructs her to kill the American delegate. The Doctor connects Chin-Lee with the Chinese assistant seen working with Emil Keller when he installed the machine at Strangmoor prison. At the prison a riot has broken out instigated by Mailer, the next prisoner due to be processed. The prisoners are seizing control of the prison with Jo trapped inside. Chin-Lee summons the American delegate to the rooms of the Chinese delegation where he is confronted by a Chinese dragon!
Oh look, it's the Master behind what's going on. What a surprise. Well it is this time perhaps, and well done for keeping him absent for an episode to conceal who it is. But you wonder about the wisdom of bringing their new villain back so soon after his debut. I suppose that would be ok if it wasn't for what happened in the next three stories.... Another bit of arch name dropping here as the Doctor claims to know Mao Tse Tung!
In case you're wondering, the football scarf the Master is wearing when dressed as a telephone engineer is Black & White stripes, so given that this bit of the story is set in Kensington & Chelsea almost certainly means he's a Fulham fan rather than Newcastle. Which is a roundabout way of introducing a new piece of technical wizardry. Remember me saying about the black & white telerecordings of colour episodes needing to have a filter used to cut out the red, green & blue colour dots properly? Well on most Doctor Who episodes it wasn't. Years ago BBC technician James Insell was watching Ambassadors of Death, a story notoriously difficult to colour restore from domestic colour recordings, in black & white on UK gold and noticed occasional flashes of colour. Theorising that the transmission system was attempting to decode the accidentally embedded colour information he began work on a system to correctly decode it. Joined by a number of other technically minded people the system has been improved to a level where the original colour can now be extracted from black & white telerecordings! I'm sorry this does my head in, it's the closest thing to necromancy you'll find. Colour from a black and white picture? Madness. But it works and has already been used on a DVD release, for Planet of the Daleks 3, where it was combined with other methods to produce a near perfect copy of the previously black & white only episode 3.